ALTR / Altair Engineering Inc. - Pengajuan SECLaporan Tahunan, Pernyataan Proksi

Altair Engineering Inc.
US ˙ NasdaqGS ˙ US0213691035
HINDI NA ACTIVE ANG SIMBONG ITO

Mga Batayang Estadistika
LEI 549300FJ89HZ6GU9S994
CIK 1701732
SEC Filings
All companies that sell securities in the United States must register with the Securities and Exchange Commission (SEC) and file reports on a regular basis. These reports include company annual reports (10K, 10Q), news updates (8K), investor presentations (found in 8Ks), insider trades (form 4), ownership reports (13D, and 13G), and reports related to the specific securities sold, such as registration statements and prospectus. This page shows recent SEC filings related to Altair Engineering Inc.
SEC Filings (Chronological Order)
Halaman ini menyediakan daftar lengkap dan kronologis dari Pengajuan SEC, tidak termasuk pengajuan kepemilikan yang kami sediakan di tempat lain.
April 7, 2025 15-12G

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 15 CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13

15-12G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 15 CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13 AND 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934. Commission File Number 001-38263 ALTAIR ENGINEERING INC. (Exact name of registrant as specif

March 28, 2025 EX-3.1

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION ALTAIR ENGINEERING INC. ARTICLE I

Exhibit 3.1 AMENDED AND RESTATED CERTIFICATE OF INCORPORATION OF ALTAIR ENGINEERING INC. ARTICLE I The name of the Corporation is Altair Engineering Inc. (the “Corporation”). ARTICLE II The address of the Corporation’s registered office in the State of Delaware is 1209 Orange Street, Wilmington, County of New Castle, Delaware, 19801. The name of its registered agent at such address is The Corporat

March 28, 2025 EX-3.2

BYLAWS ALTAIR ENGINEERING INC. ARTICLE I

Exhibit 3.2 BYLAWS OF ALTAIR ENGINEERING INC. ARTICLE I Offices Section 1.01 Registered Office. The registered office of the Corporation shall be established and maintained at the office of The Corporation Trust Company, 1209 Orange Street, Wilmington, Delaware, 19801, and said corporation shall be the Registered Agent of this Corporation in charge thereof. Section 1.02 Other Offices. The Corporat

March 28, 2025 8-K

Changes in Control of Registrant, Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Entry into a Material Definitive Agreement, Termination of a Material Definitive Agreement, Material Modification to Rights of Security Holders, Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing, Triggering Events That Accelerate or Increase a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement, Completion of Acquisition or Disposition of Assets

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 26, 2025 Altair Engineering Inc. (Exact Name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission

March 28, 2025 EX-4.1

FIRST SUPPLEMENTAL INDENTURE

Exhibit 4.1 FIRST SUPPLEMENTAL INDENTURE FIRST SUPPLEMENTAL INDENTURE (the “Supplemental Indenture”), dated as of March 26, 2025, between ALTAIR ENGINEERING INC., a Delaware corporation, as issuer (the “Company”), and U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, a national banking association, as trustee (the “Trustee”), to the Indenture, dated as of June 14, 2022 (as supplemented or otherwise m

March 26, 2025 POSASR

As filed with the Securities and Exchange Commission on March 26, 2025

As filed with the Securities and Exchange Commission on March 26, 2025 Registration Statement No.

March 26, 2025 S-8 POS

As filed with the Securities and Exchange Commission on March 26, 2025

S-8 POS As filed with the Securities and Exchange Commission on March 26, 2025 Registration Statement No.

March 26, 2025 S-8 POS

As filed with the Securities and Exchange Commission on March 26, 2025

S-8 POS As filed with the Securities and Exchange Commission on March 26, 2025 Registration Statement No.

March 26, 2025 S-8 POS

As filed with the Securities and Exchange Commission on March 26, 2025

S-8 POS As filed with the Securities and Exchange Commission on March 26, 2025 Registration Statement No.

March 26, 2025 S-8 POS

As filed with the Securities and Exchange Commission on March 26, 2025

S-8 POS As filed with the Securities and Exchange Commission on March 26, 2025 Registration Statement No.

March 26, 2025 S-8 POS

As filed with the Securities and Exchange Commission on March 26, 2025

S-8 POS As filed with the Securities and Exchange Commission on March 26, 2025 Registration Statement No.

March 26, 2025 S-8 POS

As filed with the Securities and Exchange Commission on March 26, 2025

S-8 POS As filed with the Securities and Exchange Commission on March 26, 2025 Registration Statement No.

March 26, 2025 S-8 POS

As filed with the Securities and Exchange Commission on March 26, 2025

S-8 POS As filed with the Securities and Exchange Commission on March 26, 2025 Registration Statement No.

March 26, 2025 S-8 POS

As filed with the Securities and Exchange Commission on March 26, 2025

S-8 POS As filed with the Securities and Exchange Commission on March 26, 2025 Registration Statement No.

March 25, 2025 10-K/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A (Amendment No. 1) (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 or ☐ T

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A (Amendment No. 1) (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from       to       Commission file

February 20, 2025 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-382

February 20, 2025 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 20, 2025 Altair Engineering Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commissi

February 20, 2025 EX-99.1

Altair Announces Fourth Quarter and Full Year 2024 Financial Results

Exhibit 99.1 Altair Announces Fourth Quarter and Full Year 2024 Financial Results TROY, Mich. – February 20, 2025 – Altair (Nasdaq: ALTR), a global leader in computational intelligence, today released its financial results for the fourth quarter and full year ended December 31, 2024. Fourth Quarter 2024 Financial Highlights • Software revenue was $179.4 million compared to $155.9 million for the f

February 20, 2025 EX-19.1

Insider Trading Policy

Exhibit 19.1 POLICY ON INSIDER TRADING This Policy on Insider Trading (the “Policy”), is designed to prevent insider trading or allegations of insider trading, and to protect Altair Engineering Inc.’s reputation for integrity and ethical conduct. This Policy applies to all directors, officers and employees of Altair Engineering Inc., its subsidiaries and affiliates (collectively, “Altair”). The Sp

February 20, 2025 EX-21.1

List of Subsidiaries of the Registrant

Exhibit 21.1 LIST OF SUBSIDIARIES Subsidiaries of the Registrant as of December 31, 2024 Jurisdiction of Organization Altair Engineering, Inc. United States Datawatch Corporation United States Altair Product Design, Inc. United States Ilumisys Inc. United States Altair Bellingham LLC United States Altair Bellingham II, LLC United States Altair Bellingham III, LLC United States RapidMiner, Inc. Uni

January 22, 2025 EX-99.1

Altair Engineering Inc. Stockholders Approve Proposed Merger with Siemens

Exhibit 99.1 Altair Engineering Inc. Stockholders Approve Proposed Merger with Siemens TROY, Mich., January 22, 2025 – Altair Engineering Inc. (“Altair”) (Nasdaq: ALTR), a global leader in computational intelligence, today announced that its stockholders voted at a special meeting to adopt the merger agreement with Siemens Industry Software Inc. (“Siemens Industry”), a subsidiary of Siemens AG (“S

January 22, 2025 8-K

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 22, 2025 Altair Engineering Inc. (Exact Name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commissio

January 16, 2025 8-K

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 16, 2025 Altair Engineering Inc. (Exact Name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commissio

January 16, 2025 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 16, 2025 Altair Engineeri

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 16, 2025 Altair Engineering Inc. (Exact Name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commissio

December 18, 2024 DEFM14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a 6(e)(2)) ☒ Defi

December 4, 2024 PREM14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☒ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a 6(e)(2)) ☐ Defi

December 4, 2024 EX-FILING FEES

CALCULATION OF FILING FEE TABLES Schedule 14A (Form Type) Altair Engineering Inc. (Exact Name of Registrant as Specified in its Charter ) Table 1: Transaction Valuation Proposed Maximum Aggregate Value of Transaction Fee rate Amount of Filing Fee Fee

CALCULATION OF FILING FEE TABLES Schedule 14A (Form Type) Altair Engineering Inc. (Exact Name of Registrant as Specified in its Charter ) Table 1: Transaction Valuation Proposed Maximum Aggregate Value of Transaction Fee rate Amount of Filing Fee Fees to be Paid $10,640,604,429.20 (1) 0.0001531 $1,629,077 (2) Fees Previously Paid $0 $0 Total Transaction Valuation $10,640,604,429.20 Total Fees Due

November 21, 2024 SC 13G

ALTR / Altair Engineering Inc. / PICTET ASSET MANAGEMENT SA - SC 13G Passive Investment

SC 13G 1 d872995dsc13g.htm SC 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* Altair Engineering Inc (Name of Issuer) CLASS A (Title of Class of Securities) 021369103 (CUSIP Number) 2024/09/30 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pu

November 21, 2024 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Proxy State

November 19, 2024 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Proxy State

November 13, 2024 SC 13G/A

ALTR / Altair Engineering Inc. / Matrix Capital Management Company, LP - ALTAIR ENGINEERING, INC. Passive Investment

SC 13G/A 1 p24-3328sc13ga.htm ALTAIR ENGINEERING, INC. SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G/A Under the Securities Exchange Act of 1934 (Amendment No. 5)* Altair Engineering, Inc. (Name of Issuer) Class A Common Stock, $0.0001 par value per share (Title of Class of Securities) 021369103 (CUSIP Number) September 30, 2024 (Date of Event Which Requires Filing of this

November 8, 2024 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Proxy State

November 8, 2024 SC 13G/A

ALTR / Altair Engineering Inc. / Scapa James Ralph - SC 13G/A Passive Investment

SC 13G/A 1 d896236dsc13ga.htm SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 7)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 021369103 (CUSIP Number) September 30, 2024 (Date of Event Which Requires Filing of this Stat

November 8, 2024 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Proxy State

November 8, 2024 SC 13G/A

ALTR / Altair Engineering Inc. / Christ George J - SC 13G/A Passive Investment

SC 13G/A 1 d881748dsc13ga.htm SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 7)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 021369103 (CUSIP Number) September 30, 2024 (Date of Event Which Requires Filing of this Stat

November 7, 2024 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Proxy State

November 4, 2024 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934

DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Pro

October 31, 2024 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2024 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERI

October 31, 2024 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Proxy State

October 31, 2024 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant  ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Proxy Stat

October 30, 2024 EX-10.1

Voting Agreement, dated as of October 30, 2024, by and among Siemens Industry Software Inc., Altair Engineering Inc., James R. Scapa, The James R. Scapa Declaration of Trust and the JRS Investments, LLC

Exhibit 10.1 Execution Version VOTING AND SUPPORT AGREEMENT This VOTING AND SUPPORT AGREEMENT (this “Agreement”), dated as of October 30, 2024, is by and among Siemens Industry Software Inc., a Delaware corporation (“Parent”), Altair Engineering Inc., a Delaware corporation (the “Company”), and the Persons listed on Schedule A hereto (each, a “Stockholder” and, collectively, the “Stockholders”). C

October 30, 2024 8-K

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 30, 2024 Altair Engineering Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commissio

October 30, 2024 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 30, 2024 Altair Engineeri

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 30, 2024 Altair Engineering Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commissio

October 30, 2024 EX-10.2

Deed of Guarantee, dated as of October 30, 2024, by and between Siemens AG and Altair Engineering Inc.

Exhibit 10.2 Execution Version Altair Engineering Inc. 1820 East Big Beaver Road Troy, Michigan 48083 USA To the attention of Mr. James R. Scapa, Chairman of the Board and Chief Executive Officer This DEED is dated October 30, 2024 Parent Company Guarantee Deed The parties agree hereby agree as follows: Siemens AG (“Siemens Parent”) is the ultimate parent of Siemens Industry Software Inc. (“Siemen

October 30, 2024 DFAN14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☐ Filed by a party other than the Registrant ☒ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Proxy State

October 30, 2024 EX-99.1

Altair Announces Third Quarter 2024 Financial Results

Exhibit 99.1 Altair Announces Third Quarter 2024 Financial Results TROY, Mich. – October 30, 2024 – Altair (Nasdaq: ALTR), today released its financial results for the third quarter and nine months ended September 30, 2024. Immediately prior to the dissemination of this press release, Altair issued a press release announcing that it has entered into a merger agreement with a subsidiary of Siemens

October 30, 2024 EX-99.1

Altair Signs Definitive Agreement with Siemens to be Acquired for $10.6 Billion Altair Stockholders to Receive $113 Per Share in Cash

Exhibit 99.1 Altair Signs Definitive Agreement with Siemens to be Acquired for $10.6 Billion Altair Stockholders to Receive $113 Per Share in Cash TROY, Mich., Oct. 30, 2024 /PRNewswire/ — Altair (Nasdaq: ALTR), a global leader in computational intelligence, today announced that it has entered into a definitive agreement to be acquired by Siemens, a leading technology company focused on industry,

October 30, 2024 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 30, 2024 Altair Engineeri

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 30, 2024 Altair Engineering Inc. (Exact Name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commissio

October 30, 2024 EX-2.1

Agreement and Plan of Merger, dated as of October 30, 2024, among Altair Engineering Inc., Siemens Industry Software Inc. and Astra Merger Sub Inc.

Exhibit 2.1 Execution Version AGREEMENT AND PLAN OF MERGER dated as of October 30, 2024 among ALTAIR ENGINEERING INC., SIEMENS INDUSTRY SOFTWARE INC. and ASTRA MERGER SUB INC. TABLE OF CONTENTS PAGE ARTICLE 1 DEFINITIONS Section 1.01. Definitions 2 Section 1.02. Other Definitional and Interpretative Provisions 15 ARTICLE 2 THE MERGER Section 2.01. The Merger 16 Section 2.02. Conversion of Shares 1

October 30, 2024 DFAN14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☐ Filed by a party other than the Registrant ☒ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Proxy State

October 30, 2024 8-K

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 30, 2024 Altair Engineering Inc. (Exact Name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commissio

September 12, 2024 CORRESP

Altair Engineering Inc. 1820 E Big Beaver Road Troy, Michigan 48083 September 12, 2024

Altair Engineering Inc. 1820 E Big Beaver Road Troy, Michigan 48083 September 12, 2024 Division of Corporation Finance Office of Technology U.S. Securities and Exchange Commission 100 F Street, N.E. Washington, D.C. 20549 Attn: Brittany Ebbertt and Melissa Kindelan Re: Altair Engineering Inc. Form 10-K for the year ended December 31, 2023 Form 8-K dated August 1, 2024 File No. 001-38263 This lette

August 1, 2024 EX-99.1

Altair Announces Second Quarter 2024 Financial Results Altair Exceeds Revenue Expectations for the Second Quarter

Exhibit 99.1 Altair Announces Second Quarter 2024 Financial Results Altair Exceeds Revenue Expectations for the Second Quarter TROY, Mich. – August 1, 2024 – Altair (Nasdaq: ALTR), a global leader in computational intelligence, today released its financial results for the second quarter and six months ended June 30, 2024. “Altair maintained its strong trajectory during the second quarter, with sof

August 1, 2024 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2024 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERING IN

August 1, 2024 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 01, 2024 Altair Engineering Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commission

June 4, 2024 8-K

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 3, 2024 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission Fi

May 16, 2024 8-K

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 16, 2024 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission Fi

May 2, 2024 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2024 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERING I

May 2, 2024 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 02, 2024 Altair Engineering Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commission Fi

May 2, 2024 EX-99.1

Altair Announces First Quarter 2024 Financial Results Altair Achieves Record Software Revenue and Total Revenue for the First Quarter

Exhibit 99.1 Altair Announces First Quarter 2024 Financial Results Altair Achieves Record Software Revenue and Total Revenue for the First Quarter TROY, Mich. – May 2, 2024 – Altair (Nasdaq: ALTR), a global leader in computational science and artificial intelligence, today released its financial results for the first quarter ended March 31, 2024. “Altair continued its positive momentum into the st

April 5, 2024 DEF 14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.)

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a

April 5, 2024 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Defini

February 22, 2024 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 22, 2024 Altair Engineering Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commissi

February 22, 2024 EX-99.1

Altair Announces Fourth Quarter and Full Year 2023 Financial Results Record-High Revenue and Profit for the Fourth Quarter and Full Year

Exhibit 99.1 Altair Announces Fourth Quarter and Full Year 2023 Financial Results Record-High Revenue and Profit for the Fourth Quarter and Full Year TROY, Mich. – February 22, 2024 – Altair (Nasdaq: ALTR), a global leader in computational intelligence, today released its financial results for the fourth quarter and full year ended December 31, 2023. "Altair finished 2023 with a strong fourth quar

February 22, 2024 EX-21.1

List of Subsidiaries of the Registrant

Exhibit 21.1 LIST OF SUBSIDIARIES Subsidiaries of the Registrant as of December 31, 2023 Jurisdiction of Organization Altair Engineering, Inc. United States Datawatch Corporation United States Altair Product Design, Inc. United States Ilumisys Inc. United States Altair Bellingham LLC United States Altair Bellingham II, LLC United States Altair Bellingham III, LLC United States RapidMiner, Inc. Uni

February 22, 2024 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2023 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-382

February 22, 2024 S-8

As filed with the Securities and Exchange Commission on February 22, 2024

As filed with the Securities and Exchange Commission on February 22, 2024 Registration No.

February 22, 2024 EX-FILING FEES

Filing Fee Table

Exhibit 107 CALCULATION OF FILING FEE TABLE Form S-8 (Form Type) Altair Engineering Inc.

February 22, 2024 EX-97

Altair Engineering Inc. Compensation Recovery Policy

Exhibit 97 ALTAIR ENGINEERING INC. (Adopted and approved on August 9, 2023, and effective as of December 1, 2023) 1. Purpose Altair Engineering Inc. (collectively with its subsidiaries, the “Company”) is committed to promoting high standards of honest and ethical business conduct and compliance with applicable laws, rules and regulations. As part of this commitment, the Company has adopted this Co

February 13, 2024 SC 13G/A

ALTR / Altair Engineering Inc. / Christ George J - SC 13G/A Passive Investment

SC 13G/A 1 d764075dsc13ga.htm SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 6)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2023 (Date of Event Which Requires Filing of this State

February 13, 2024 SC 13G/A

ALTR / Altair Engineering Inc. / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SC 13G/A 1 tv0240-altairengineeringincc.htm SCHEDULE 13G/A SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 6)* Name of issuer: Altair Engineering Inc. Class A Title of Class of Securities: Common Stock CUSIP Number: 021369103 Date of Event Which Requires Filing of this Statement: December 29, 2023 Check the appropriat

February 13, 2024 SC 13G/A

ALTR / Altair Engineering Inc. / Scapa James Ralph - SC 13G/A Passive Investment

SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 6)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2023 (Date of Event Which Requires Filing of this Statement) Check the appropriate bo

February 13, 2024 SC 13G/A

ALTR / Altair Engineering Inc. / Matrix Capital Management Company, LP - ALTAIR ENGINEERING, INC. Passive Investment

SC 13G/A 1 p24-0533sc13ga.htm ALTAIR ENGINEERING, INC. SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G/A Under the Securities Exchange Act of 1934 (Amendment No. 4)* Altair Engineering, Inc. (Name of Issuer) Class A Common Stock, $0.0001 par value per share (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2023 (Date of Event Which Requires Filing of this

November 2, 2023 EX-99.1

Altair Announces Third Quarter 2023 Financial Results Quarterly Software Product Revenue Increased more than 14% Year-Over-Year

Exhibit 99.1 Altair Announces Third Quarter 2023 Financial Results Quarterly Software Product Revenue Increased more than 14% Year-Over-Year TROY, Mich. – November 2, 2023 – Altair (Nasdaq: ALTR), a global leader in computational science and artificial intelligence, today released its financial results for the third quarter and nine months ended September 30, 2023. "The third quarter of 2023 was e

November 2, 2023 EX-10.1

Executive Severance Agreement, dated as of July 25, 2023, by and between Ravi Kunju and the Company

Exhibit 10.1 EXECUTIVE SEVERANCE AGREEMENT THIS EXECUTIVE SEVERANCE AGREEMENT (as amended, restated, or otherwise modified from time to time, this “Agreement”), dated as of July 25, 2023 (the “Effective Date”), is entered into by and between Altair Engineering Inc., a Delaware corporation (the “Company”), and Ravi Kunju (the “Executive”). W I T N E S S E T H: WHEREAS, the Executive currently serve

November 2, 2023 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 02, 2023 Altair Engineering Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commissi

November 2, 2023 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERI

August 3, 2023 EX-99.1

Altair Announces Second Quarter 2023 Financial Results Software Product Revenue and Total Revenue Above the High End of Guidance Range

Exhibit 99.1 Altair Announces Second Quarter 2023 Financial Results Software Product Revenue and Total Revenue Above the High End of Guidance Range TROY, Mich. – August 3, 2023 – Altair (Nasdaq: ALTR), a global leader in computational science and artificial intelligence, today released its financial results for the second quarter and six months ended June 30, 2023. “Altair had a solid second quart

August 3, 2023 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERING IN

August 3, 2023 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 03, 2023 Altair Engineering Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commission

August 2, 2023 CORRESP

Altair Engineering Inc. 1820 E Big Beaver Road Troy, Michigan 48083

Altair Engineering Inc. 1820 E Big Beaver Road Troy, Michigan 48083 August 2, 2023 Division of Corporation Finance Office of Technology U.S. Securities and Exchange Commission 100 F Street, N.E. Washington, D.C. 20549 Attn: Edwin Kim, Esq. and Mitchell Austin, Esq. Re: Altair Engineering Inc. Form 10-Q for the Fiscal Quarter Ended March 31, 2023 Filed May 4, 2023 File No. 001-38263 Dear Ladies and

July 11, 2023 CORRESP

Altair Engineering Inc. 1820 E Big Beaver Road Troy, Michigan 48083 July 11, 2023

Altair Engineering Inc. 1820 E Big Beaver Road Troy, Michigan 48083 July 11, 2023 Division of Corporation Finance Office of Technology U.S. Securities and Exchange Commission 100 F Street, N.E. Washington, D.C. 20549 Attn: Edwin Kim, Esq. and Mitchell Austin, Esq. Re: Altair Engineering Inc. Form 10-Q for the Fiscal Quarter Ended March 31, 2023 Filed May 4, 2023 File No. 001-38263 This letter is s

June 9, 2023 SC 13G/A

ALTR / Altair Engineering Inc - Class A / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SC 13G/A 1 tv0016-altairengineeringincc.htm SCHEDULE 13G/A SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 5)* Name of issuer: Altair Engineering Inc. Class A Title of Class of Securities: Common Stock CUSIP Number: 021369103 Date of Event Which Requires Filing of this Statement: May 31, 2023 Check the appropriate box

June 8, 2023 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 6, 2023 Altair Engineering I

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 6, 2023 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission Fi

May 31, 2023 8-K

Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 31, 2023 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission Fi

May 4, 2023 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERING I

May 4, 2023 EX-99

Altair Announces First Quarter 2023 Financial Results Altair Exceeds Expectations and Achieves All-Time High Revenue

Exhibit 99.1 Altair Announces First Quarter 2023 Financial Results Altair Exceeds Expectations and Achieves All-Time High Revenue TROY, Mich. – May 4, 2023 – Altair (Nasdaq: ALTR), a global leader in computational science and artificial intelligence, today released its financial results for the first quarter ended March 31, 2023. “Altair had a very strong start to 2023, with software product reven

May 4, 2023 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 04, 2023 Altair Engineering Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commission Fi

April 25, 2023 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.)

DEFA14A 1 d421123ddefa14a.htm DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as p

April 25, 2023 DEF 14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☒ Defini

February 24, 2023 EX-4

Description of Capital Stock

Exhibit 4.1 Description of the Registrant’s Capital Stock General The following is a summary of the rights of our Class A and Class B common stock and preferred stock. This summary is qualified in its entirety by the provisions of our certificate of incorporation and bylaws, copies of which are filed as exhibits to the Annual Report of which this Exhibit is a part of. Our authorized capital stock

February 24, 2023 EX-21

List of Subsidiaries of the Registrant

Exhibit 21.1 LIST OF SUBSIDIARIES Subsidiaries of the Registrant as of December 31, 2022 Jurisdiction of Organization Altair Engineering, Inc. United States Datawatch Corporation United States Altair Product Design, Inc. United States Ilumisys Inc. United States Altair Bellingham LLC United States Altair Bellingham II, LLC United States Altair Bellingham III, LLC United States Powersim, LLC United

February 24, 2023 EX-10

Executive Severance Agreement, dated March 5, 2021, by and between Altair Engineering Inc., and Mahalingam Srikanth

Exhibit 10.26 Exhibit 10.26 EXECUTIVE SEVERANCE AGREEMENT THIS EXECUTIVE SEVERANCE AGREEMENT (as amended, restated, or otherwise modified from time to time, this "Agreement"), dated as of the 5th day of March, 2021 (the "Effective Date"), is entered into by and between Altair Engineering Inc., a Delaware corporation (the "Company"), and Mahalingam Srikanth (the "Executive"). W I T N E S S E T H: W

February 24, 2023 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-382

February 23, 2023 EX-99

Altair Announces Fourth Quarter and Full Year 2022 Financial Results Altair Achieves Record-High Revenue for 2022 and Outperforms Guidance Measures

Exhibit 99.1 Altair Announces Fourth Quarter and Full Year 2022 Financial Results Altair Achieves Record-High Revenue for 2022 and Outperforms Guidance Measures TROY, Mich. – February 23, 2023 – Altair (Nasdaq: ALTR), a global leader in computational science and artificial intelligence, today released its financial results for the fourth quarter and full year ended December 31, 2022. “Altair had a

February 23, 2023 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 23, 2023 Altair Engineering Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commissi

February 13, 2023 SC 13G/A

ALTR / Altair Engineering Inc / Matrix Capital Management Company, LP - ALTAIR ENGINEERING, INC. Passive Investment

SC 13G/A 1 p23-0753sc13ga.htm ALTAIR ENGINEERING, INC. SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G/A Under the Securities Exchange Act of 1934 (Amendment No. 3)* Altair Engineering, Inc. (Name of Issuer) Class A Common Stock, $0.0001 par value per share (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2022 (Date of Event Which Requires Filing of this

February 9, 2023 SC 13G/A

ALTR / Altair Engineering Inc / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SC 13G/A 1 tv0216-altairengineeringincc.htm SCHEDULE 13G/A SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 4)* Name of issuer: Altair Engineering Inc. Class A Title of Class of Securities: Common Stock CUSIP Number: 021369103 Date of Event Which Requires Filing of this Statement: December 30, 2022 Check the appropriat

February 6, 2023 SC 13G/A

ALTR / Altair Engineering Inc / Scapa James Ralph - SC 13G/A Passive Investment

SC 13G/A 1 d405549dsc13ga.htm SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 5)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2022 (Date of Event Which Requires Filing of this State

February 6, 2023 SC 13G/A

ALTR / Altair Engineering Inc / Christ George J - SC 13G/A Passive Investment

SC 13G/A 1 d398129dsc13ga.htm SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 5)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2022 (Date of Event Which Requires Filing of this State

January 4, 2023 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 30, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissi

January 4, 2023 EX-10.1

Employment Separation and General Release Agreement, dated as of December 30, 2022, by and between Dr. Uwe Schramm and the Company

Exhibit 10.1 EMPLOYMENT SEPARATION AND GENERAL RELEASE AGREEMENT This Employment Separation and General Release Agreement (?Agreement?) is made as of the date of last signature below, by and between UWE SCHRAMM a resident of the State of California (?EMPLOYEE?), and ALTAIR ENGINEERING INC., a Delaware corporation (?EMPLOYER?). EMPLOYEE and EMPLOYER agree to conclude their existing employment relat

November 10, 2022 8-K

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 7, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissio

November 4, 2022 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2022 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERI

November 3, 2022 EX-99.1

Altair Announces Third Quarter 2022 Financial Results Altair Beats Third Quarter Expectations, Raises Full Year Guidance in Constant Currency

Exhibit 99.1 Altair Announces Third Quarter 2022 Financial Results Altair Beats Third Quarter Expectations, Raises Full Year Guidance in Constant Currency TROY, Mich. ? November 3, 2022 ? Altair (Nasdaq: ALTR), a global leader in computational science and artificial intelligence (AI), today released its financial results for the third quarter ended September 30, 2022. ?Altair had a solid third qua

November 3, 2022 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 03, 2022 Altair Engineering Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commissi

October 3, 2022 EX-10.1

Employment Separation and General Release Agreement, dated as of September 30, 2022, by and between Brett Chouinard and the Company

Exhibit 10.1 EMPLOYMENT SEPARATION AND GENERAL RELEASE AGREEMENT This Employment Separation and General Release Agreement (?Agreement?) is made as of September 30, 2022, by and between BRETT CHOUINARD a resident of the State of Michigan (?EMPLOYEE?), and ALTAIR ENGINEERING INC., a Delaware corporation (?EMPLOYER?). EMPLOYEE and EMPLOYER agree to conclude their existing employment relationship as o

October 3, 2022 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 30, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commiss

September 16, 2022 EX-99.1

Altair Announces Completion of Acquisition of RapidMiner

Exhibit 99.1 Altair Announces Completion of Acquisition of RapidMiner TROY, Mich., Sept. 16 2022 ? Altair (Nasdaq: ALTR), a global leader in computational science and artificial intelligence (AI), has completed the acquisition of RapidMiner, a leader in advanced data analytics and machine learning (ML) software. RapidMiner?s well-established desktop platform and new-to-market cloud platform (multi

September 16, 2022 8-K

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 16, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commiss

September 13, 2022 EX-2.1

Agreement and Plan of Merger, dated as of September 13, 2022, by and among the Company, RapidMiner, Inc., Rambler Merger Sub Inc., and the Shareholder Representative Services LLC

Exhibit 2.1 AGREEMENT AND PLAN OF MERGER This Agreement and Plan of Merger (this ?Agreement?), dated as of September 13, 2022, is entered into by and among Altair Engineering Inc., a Delaware corporation (the ?Purchaser?), Rambler Merger Sub Inc., a Delaware corporation and a wholly owned subsidiary of the Purchaser (the ?Merger Sub?), RapidMiner, Inc., a Delaware corporation (the ?Company?), and

September 13, 2022 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 13, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commiss

August 23, 2022 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 17, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission

August 5, 2022 S-3ASR

As filed with the Securities and Exchange Commission on August 5, 2022

Table of Contents As filed with the Securities and Exchange Commission on August 5, 2022 Registration No.

August 5, 2022 EX-FILING FEES

Calculation of Filing Fee Table.

Exhibit 107 Calculation of Filing Fee Table Form S-3 (Form Type) Altair Engineering Inc.

August 4, 2022 EX-99.1

Altair Announces Second Quarter 2022 Financial Results Altair Beats Second Quarter Expectations

Exhibit 99.1 Altair Announces Second Quarter 2022 Financial Results Altair Beats Second Quarter Expectations TROY, Mich. ? August 4, 2022 ? Altair (Nasdaq: ALTR), a global leader in computational science and artificial intelligence (AI) that provides software and cloud solutions in simulation, high-performance computing (HPC), data analytics and AI, today released its financial results for the sec

August 4, 2022 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 04, 2022 Altair Engineering Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38263 38-2591828 (State or Other Jurisdiction of Incorporation) (Commission

August 4, 2022 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2022 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERING IN

June 30, 2022 CORRESP

Altair Engineering Inc. 1820 E Big Beaver Road Troy, Michigan 48083

Altair Engineering Inc. 1820 E Big Beaver Road Troy, Michigan 48083 June 30, 2022 Division of Corporation Finance U.S. Securities and Exchange Commission 100 F Street, N.E. Washington, D.C. 20549 Attention: Christine Dietz Kathleen Collins Re: Altair Engineering Inc. Form 10-K for the Fiscal Year Ended December 31, 2021 Filed February 28, 2022 Form 8-K Furnished May 5, 2022 File No. 001-38263 Dear

June 24, 2022 8-K

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 24, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission F

June 24, 2022 EX-99.1

Altair Announces Sale of $230 Million Aggregate Principal Amount of Convertible Senior Notes

Exhibit 99.1 Altair Announces Sale of $230 Million Aggregate Principal Amount of Convertible Senior Notes TROY, Mich., June 24, 2022 /PRNewswire/ ? Altair Engineering Inc. (Nasdaq: ALTR) (?Altair?) today announced the closing of its private offering of convertible senior notes and the exercise in full of the initial purchaser?s option to purchase additional convertible senior notes. At a closing o

June 24, 2022 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 18, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission F

June 15, 2022 8-K

Entry into a Material Definitive Agreement, Unregistered Sales of Equity Securities, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 14, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission F

June 15, 2022 EX-4.1

Form of 1.750% Convertible Senior Notes due 2027 (included in Exhibit 4.1 to the Indenture, dates as of June 14, 2022, by and between Altair Engineering Inc., and U.S. Bank Trust Company National Association as trustee)

Exhibit 4.1 ALTAIR ENGINEERING INC. AND U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, as Trustee INDENTURE Dated as of June 14, 2022 1.750% Convertible Senior Notes due 2027 TABLE OF CONTENTS PAGE ARTICLE 1 DEFINITIONS Section 1.01. Definitions 1 Section 1.02. References to Interest 15 ARTICLE 2 ISSUE, DESCRIPTION, EXECUTION, REGISTRATION AND EXCHANGE OF NOTES Section 2.01. Designation and Amount

June 10, 2022 8-K

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 9, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission Fi

June 10, 2022 EX-99.2

Altair Announces Pricing of Offering of $200 Million of Convertible Senior Notes

Exhibit 99.2 Altair Announces Pricing of Offering of $200 Million of Convertible Senior Notes TROY, Mich., June 10, 2022 /PRNewswire/ ? Altair (Nasdaq: ALTR), a global leader in computational science and artificial intelligence, today announced the pricing of $200 million aggregate principal amount of Convertible Senior Notes due 2027 (the ?notes?) in a private offering (the ?offering?) to persons

June 10, 2022 EX-99.1

Altair Announces Proposed Private Offering of $200 Million of Convertible Senior Notes

Exhibit 99.1 Altair Announces Proposed Private Offering of $200 Million of Convertible Senior Notes TROY, Mich., June 9, 2022 /PRNewswire/ ? Altair (Nasdaq: ALTR), a global leader in computational science and artificial intelligence, today announced its intention to offer, subject to market conditions and other factors, $200 million aggregate principal amount of Convertible Senior Notes due 2027 (

May 12, 2022 8-K

Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 11, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission Fi

May 5, 2022 EX-99.1

Altair Announces First Quarter 2022 Financial Results Altair Achieves Record Quarterly Revenue

Exhibit 99.1 Altair Announces First Quarter 2022 Financial Results Altair Achieves Record Quarterly Revenue TROY, Mich. – May 5, 2022 – Altair (Nasdaq: ALTR), a global leader in computational science and artificial intelligence (AI) that provides software and cloud solutions in the areas of simulation, high-performance computing (HPC), data analytics and AI, today released its financial results fo

May 5, 2022 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERING I

May 5, 2022 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 5, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission Fil

March 30, 2022 DEF 14A

Schedule 14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.) Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Defini

March 30, 2022 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.) Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Defini

March 1, 2022 S-8

As filed with the Securities and Exchange Commission on February 28, 2022

As filed with the Securities and Exchange Commission on February 28, 2022 Registration No.

March 1, 2022 EX-FILING FEES

Filing Fee Table

Exhibit 107.1 CALCULATION OF FILING FEE TABLE Form S-8 (Form Type) Altair Engineering Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Title of securities to be registered Fee Calculation Rule Amount to be registered(1) Proposed maximum offering price per share(2) Proposed maximum aggregate offering price(2) Fee Rate Amount of registrat

February 28, 2022 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2021 or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-38263 ALTAIR ENGINEER

February 28, 2022 EX-21.1

List of Subsidiaries of the Registrant

Exhibit 21.1 LIST OF SUBSIDIARIES Subsidiary Jurisdiction of Organization Altair Engineering, Inc. Delaware, United States Altair Engineering Ltd. United Kingdom Datawatch Corporation Delaware, United States World Programming Limited United Kingdom

February 24, 2022 EX-99.1

Altair Announces Fourth Quarter and Full Year 2021 Financial Results Full Year 2021 Software Product Revenue Grew 15.8%, Exceeding Expectations

Exhibit 99.1 Altair Announces Fourth Quarter and Full Year 2021 Financial Results Full Year 2021 Software Product Revenue Grew 15.8%, Exceeding Expectations TROY, Mich. ? February 24, 2022 ? Altair (Nasdaq: ALTR), a global leader in computational science and artificial intelligence today released its financial results for the fourth quarter and full year ended December 31, 2021. ?Altair had an exc

February 24, 2022 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 21, 2022 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissi

February 14, 2022 SC 13G/A

ALTR / Altair Engineering Inc / Matrix Capital Management Company, LP Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G/A Under the Securities Exchange Act of 1934 (Amendment No. 2)* Altair Engineering, Inc. (Name of Issuer) Class A Common Stock, $0.0001 par value per share (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2021 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the r

February 9, 2022 SC 13G/A

ALTR / Altair Engineering Inc / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 3)* Name of issuer: Altair Engineering Inc. Class A Title of Class of Securities: Common Stock CUSIP Number: 021369103 Date of Event Which Requires Filing of this Statement: December 31, 2021 Check the appropriate box to designate the rule pursuant to which this Schedule

February 8, 2022 SC 13G/A

ALTR / Altair Engineering Inc / Christ George J - SC 13G/A Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 4)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2021 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to desi

February 8, 2022 SC 13G/A

ALTR / Altair Engineering Inc / Scapa James Ralph - SC 13G/A Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 4)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2021 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to desi

December 15, 2021 8-K

Entry into a Material Definitive Agreement, Unregistered Sales of Equity Securities, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 15, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissi

December 15, 2021 EX-10.1

Stock Purchase Agreement, dated December 15, 2021, by and among the Company, its UK-based subsidiary Altair Engineering Ltd., the stockholders of World Programming Limited named therein and a sellers’ representative named therein

Exhibit 10.1 STOCK PURCHASE AGREEMENT THIS STOCK PURCHASE AGREEMENT (the ?Agreement?), dated as of December 15, 2021, is by and among: Oliver Robinson, an individual residing at the address set forth in Exhibit A annexed hereto (?Oliver Robinson?); Thomas Quarendon, an individual residing at the address set forth in Exhibit A annexed hereto (?Thomas Quarendon?); Martin Jupp, an individual residing

December 15, 2021 EX-10.2

Stock Purchase Agreement, dated December 15, 2021, by and among the Company, its UK-based subsidiary Altair Engineering Ltd., the stockholders of December 2015 Software Limited named therein and a sellers’ representative named therein

Exhibit 10.2 STOCK PURCHASE AGREEMENT THIS STOCK PURCHASE AGREEMENT (the ?Agreement?), dated as of December 15, 2021, is by and among: Oliver Robinson, an individual residing at the address set forth in Exhibit A Annexed hereto (?Oliver Robinson?); Thomas Quarendon, an individual residing at the address set forth in Exhibit A Annexed hereto (?Thomas Quarendon?); Martin Jupp, an individual residing

December 10, 2021 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 9, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissio

November 4, 2021 EX-99.1

Altair Announces Third Quarter 2021 Financial Results Exceeds Expectations for Third Quarter 2021, Raises Outlook for the Year

Exhibit 99.1 Altair Announces Third Quarter 2021 Financial Results Exceeds Expectations for Third Quarter 2021, Raises Outlook for the Year TROY, Mich. ? November 4, 2021 ? Altair (Nasdaq: ALTR), a global technology company providing software and cloud solutions in the areas of simulation, high-performance computing, data analytics and artificial intelligence today released its financial results f

November 4, 2021 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 4, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissio

November 4, 2021 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2021 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERI

September 27, 2021 EX-99.1

Altair Announces Private Placement Financing of $200 Million from Matrix Capital Management Company LP

Exhibit 99.1 Altair Announces Private Placement Financing of $200 Million from Matrix Capital Management Company LP TROY, Mich. ? September 27, 2021 ? Altair (Nasdaq: ALTR), a global technology company providing software and cloud solutions in the areas of simulation, high-performance computing, data analytics and artificial intelligence today announced a private placement financing of $200 millio

September 27, 2021 EX-10.2

Registration Rights Agreement, dated September 27, 2021, by and between the Company and the Purchaser.

Exhibit 10.2 REGISTRATION RIGHTS AGREEMENT REGISTRATION RIGHTS AGREEMENT (this ?Agreement?), dated as of September 27, 2021, by and among Altair Engineering Inc., a Delaware corporation, with headquarters located at 1820 East Big Beaver Road, Troy, Michigan 48083 (the ?Company?), and the investors listed on the Schedule of Buyers attached hereto (each, a ?Buyer? and collectively, the ?Buyers?). WH

September 27, 2021 EX-10.1

Securities Purchase Agreement, dated September 27, 2021, by and between the Company and the Purchaser.

Exhibit 10.1 SECURITIES PURCHASE AGREEMENT SECURITIES PURCHASE AGREEMENT (this ?Agreement?), dated as of September 27, 2021, by and among Altair Engineering Inc., a Delaware corporation, with headquarters located at 1820 East Big Beaver Road, Troy, Michigan 48083 (the ?Company?), and the investors listed on the Schedule of Buyers attached hereto (each, a ?Buyer? and collectively, the ?Buyers?). WH

September 27, 2021 8-K

Entry into a Material Definitive Agreement, Unregistered Sales of Equity Securities, Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 27, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commiss

August 5, 2021 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2021 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERING IN

August 5, 2021 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 5, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission

August 5, 2021 EX-99.1

Altair Announces Second Quarter 2021 Financial Results Exceeds Expectations for Second Quarter 2021, Raises Outlook for the Year

Exhibit 99.1 Altair Announces Second Quarter 2021 Financial Results Exceeds Expectations for Second Quarter 2021, Raises Outlook for the Year TROY, Mich. ? August 5, 2021 ? Altair (Nasdaq: ALTR), a global technology company providing software and cloud solutions in the areas of simulation, high-performance computing, data analytics and artificial intelligence today released its financial results f

July 16, 2021 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 13, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission F

June 2, 2021 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits, Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 2, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission Fi

May 20, 2021 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Definitive Proxy State

May 13, 2021 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Definitive Proxy State

May 13, 2021 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Definitive Proxy State

May 6, 2021 EX-10.2

Employment Letter dated December 6, 2020, by and between Altair Engineering Inc. and Matthew Brown

EXHIBIT 10.2 CONFIDENTIAL December 6, 2020 Matt Brown Dear Matt, Altair Engineering, Inc. (?Altair? or the ?Company?) is pleased to extend to you an offer of employment (the ?Offer?). We believe that Altair can provide you with a highly competitive compensation package as well as an innovative environment where you will be able to make significant contributions to the success of the Company. The O

May 6, 2021 EX-10.5

Amended and Restated Executive Severance Agreement dated March 8, 2021, between Altair Engineering Inc. and James Scapa

EXHIBIT 10.5 AMENDED AND RESTATED EXECUTIVE SEVERANCE AGREEMENT THIS AMENDED AND RESTATED EXECUTIVE SEVERANCE AGREEMENT (as amended, restated, or otherwise modified from time to time, this ?Agreement?), dated as of the 8th day of March, 2021 (the ?Effective Date?), is entered into by and between Altair Engineering Inc., a Delaware corporation (the ?Company?), and James Scapa (the ?Executive?). W I

May 6, 2021 EX-10.7

Amended and Restated Executive Severance Agreement dated February 22, 2021, between Altair Engineering Inc. and Amy Messano

EXHIBIT 10.7 AMENDED AND RESTATED EXECUTIVE SEVERANCE AGREEMENT THIS AMENDED AND RESTATED EXECUTIVE SEVERANCE AGREEMENT (as amended, restated, or otherwise modified from time to time, this ?Agreement?), dated as of the 22nd day of February, 2021 (the ?Effective Date?), is entered into by and between Altair Engineering Inc., a Delaware corporation (the ?Company?), and Amy Messano (the ?Executive?).

May 6, 2021 10-Q

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2021 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERING I

May 6, 2021 EX-10.8

Amended and Restated Executive Severance Agreement dated February 15, 2021, between Altair Engineering Inc. and Uwe Schramm

EXHIBIT 10.8 AMENDED AND RESTATED EXECUTIVE SEVERANCE AGREEMENT THIS AMENDED AND RESTATED EXECUTIVE SEVERANCE AGREEMENT (as amended, restated, or otherwise modified from time to time, this ?Agreement?), dated as of the 15th of February, 2021 (the ?Effective Date?), is entered into by and between Altair Engineering Inc., a Delaware corporation (the ?Company?), and Uwe Schramm (the ?Executive?). W I

May 6, 2021 EX-10.3

Executive Severance Agreement dated January 26, 2021, between Altair Engineering Inc. and Matthew Brown

Exhibit 10.3 EXECUTIVE SEVERANCE AGREEMENT THIS EXECUTIVE SEVERANCE AGREEMENT (as amended, restated, or otherwise modified from time to time, this ?Agreement?), dated as of the 26th day of January, 2021 (the ?Effective Date?), is entered into by and between Altair Engineering Inc., a Delaware corporation (the ?Company?), and Matthew Brown (the ?Executive?). W I T N E S S E T H: WHEREAS, the Execut

May 6, 2021 EX-10.4

Employment Transition and Separation Agreement dated January 15, 2021, between Altair Engineering Inc. and Howard Morof

EX-10.4 4 altr-ex104191.htm EX-10.4 Exhibit 10.4 EMPLOYMENT TRANSITION AND SEPARATION AND GENERAL RELEASE AGREEMENT This Employment Transition and Separation and General Release Agreement ("Agreement") is made as of the 15th day of January, 2021 by and between HOWARD MOROF, a resident of the State of Michigan (“EMPLOYEE”), and ALTAIR ENGINEERING INC., a Delaware corporation, including all of its s

May 6, 2021 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 6, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission Fil

May 6, 2021 EX-10.6

Amended and Restated Executive Severance Agreement dated February 3, 2021, between Altair Engineering Inc. and Gilma Saravia

EXHIBIT 10.6 AMENDED AND RESTATED EXECUTIVE SEVERANCE AGREEMENT THIS AMENDED AND RESTATED EXECUTIVE SEVERANCE AGREEMENT (as amended, restated, or otherwise modified from time to time, this ?Agreement?), dated as of the 3rd day of February, 2021 (the ?Effective Date?), is entered into by and between Altair Engineering Inc., a Delaware corporation (the ?Company?), and Gilma Saravia (the ?Executive?)

May 6, 2021 EX-10.9

Amended and Restated Executive Severance Agreement dated January 31, 2021, between Altair Engineering Inc. and Brett Chouinard

EX-10.9 9 altr-ex109209.htm EX-10.9 EXHiBIT 10.9 AMENDED AND RESTATED EXECUTIVE SEVERANCE AGREEMENT THIS AMENDED AND RESTATED EXECUTIVE SEVERANCE AGREEMENT (as amended, restated, or otherwise modified from time to time, this “Agreement”), dated as of the 31st day of January, 2021 (the “Effective Date”), is entered into by and between Altair Engineering Inc., a Delaware corporation (the “Company”),

May 6, 2021 EX-99.1

Altair Announces First Quarter 2021 Financial Results Delivers Record Software Revenue and Total Revenue, Exceeding Expectations

Exhibit 99.1 Altair Announces First Quarter 2021 Financial Results Delivers Record Software Revenue and Total Revenue, Exceeding Expectations TROY, Mich. ? May 6, 2021 ? Altair (Nasdaq: ALTR), a global technology company providing software and cloud solutions in the areas of simulation, high-performance computing, data analytics and artificial intelligence today released its financial results for

April 9, 2021 S-8

- S-8

As filed with the Securities and Exchange Commission on April 9, 2021 Registration No.

April 9, 2021 DEF 14A

Altair Engineering Inc. Employee Stock Purchase Plan (incorporated by reference to Appendix B to the Company’s Definitive Proxy Statement filed with the SEC on April 9, 2021 (file number 001-38263)).

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Defi

April 9, 2021 S-8

- S-8

As filed with the Securities and Exchange Commission on April 9, 2021 Registration No.

April 9, 2021 DEFA14A

- DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Definitive Proxy State

March 17, 2021 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 17, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission

February 26, 2021 EX-21.1

List of Subsidiaries of the Registrant

Exhibit 21.1 LIST OF SUBSIDIARIES Subsidiary Jurisdiction of Organization Altair Product Design, Inc. Michigan, United States Altair Engineering India Pvt. Ltd. India Altair Engineering Ltd. Japan Datawatch Corporation Delaware, United States

February 26, 2021 10-K

Annual Report - 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-38263 ALTAIR ENGINEER

February 25, 2021 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 25, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissi

February 25, 2021 EX-99.1

Altair Announces Fourth Quarter 2020 Financial Results Record Fourth Quarter and Full Year 2020 Software Product and Total Revenue, Exceeding Expectations

EX-99.1 2 altr-ex9916.htm EX-99.1 Exhibit 99.1 Altair Announces Fourth Quarter 2020 Financial Results Record Fourth Quarter and Full Year 2020 Software Product and Total Revenue, Exceeding Expectations TROY, Mich. – February 25, 2021 – Altair (Nasdaq: ALTR), a global technology company providing software and cloud solutions in the areas of simulation, high-performance computing, data analytics and

February 16, 2021 SC 13G/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 3)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Cla

SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 3)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate bo

February 16, 2021 SC 13G/A

Altair Engineering, Inc.

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G/A Under the Securities Exchange Act of 1934 (Amendment No. 1)* Altair Engineering, Inc. (Name of Issuer) Class A Common Stock, $0.0001 par value per share (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the r

February 16, 2021 SC 13G/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 3)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Cla

SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 3)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate bo

February 11, 2021 SC 13G/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 03)* Altair Engineering Inc. (Name of Issuer) (Title of Class of Securities) (CUSIP Number) December 31, 202

Schedule 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 03)* Altair Engineering Inc. (Name of Issuer) Common (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to wh

February 10, 2021 SC 13G/A

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 2)*

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 2)* Name of issuer: Altair Engineering Inc. Class A Title of Class of Securities: Common Stock CUSIP Number: 021369103 Date of Event Which Requires Filing of this Statement: December 31, 2020 Check the appropriate box to designate the rule pursuant to which this Schedule

January 27, 2021 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 23, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissio

January 19, 2021 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 15, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissio

January 7, 2021 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 4, 2021 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission

January 6, 2021 SC 13G/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1)* ALTAIR ENGINEERING, INC. (Name of Issuer) (Class A) Common Stock, $0.01 Par Value (Title of Class of Sec

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1)* ALTAIR ENGINEERING, INC. (Name of Issuer) (Class A) Common Stock, $0.01 Par Value (Title of Class of Securities) 021369103 (CUSIP Number) January 06, 2021 (Date of Event which Requires Filing of this Statement) Check the appropriate box to designate the

December 8, 2020 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 4, 2020 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissio

November 5, 2020 EX-99.1

Altair Announces Third Quarter 2020 Financial Results 2020 Third Quarter Results Exceed Expectations

EX-99.1 2 altr-ex9916.htm EX-99.1 Exhibit 99.1 Altair Announces Third Quarter 2020 Financial Results 2020 Third Quarter Results Exceed Expectations TROY, Mich. – November 5, 2020 – Altair (Nasdaq: ALTR), a global technology company providing software and cloud solutions in the areas of simulation, data analytics, and high-performance computing, today released its financial results for the third qu

November 5, 2020 10-Q

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERI

November 5, 2020 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 5, 2020 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissio

September 14, 2020 8-K

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 14, 2020 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commiss

September 14, 2020 EX-99.1

Altair Acquires Univa Move Solidifies Altair’s Leadership in Workload Management and Cloud Enablement for High Performance Computing

EX-99.1 2 d856435dex991.htm EX-99.1 Exhibit 99.1 Altair Acquires Univa Move Solidifies Altair’s Leadership in Workload Management and Cloud Enablement for High Performance Computing TROY, Mich. – September 14, 2020 – Altair, (Nasdaq: ALTR) a global technology company providing solutions in data analytics, product development, and high-performance computing (HPC), today announced the acquisition of

August 17, 2020 EX-10.1

Executive Severance Agreement dated August 17, 2020 between Altair Engineering, Inc. and James R. Scapa

EX-10.1 Exhibit 10.1 EXECUTIVE SEVERANCE AGREEMENT THIS EXECUTIVE SEVERANCE AGREEMENT (as amended, restated, or otherwise modified from time to time, this “Agreement”), dated as of the 17th of August, 2020 (the “Effective Date”), is entered into by and between Altair Engineering Inc., a Delaware corporation (the “Company”), and James Scapa (the “Executive”). W I T N E S S E T H: WHEREAS, the Execu

August 17, 2020 EX-10.4

Executive Severance Agreement dated August 17, 2020 between Altair Engineering, Inc. and Amy Messano

EX-10.4 Exhibit 10.4 EXECUTIVE SEVERANCE AGREEMENT THIS EXECUTIVE SEVERANCE AGREEMENT (as amended, restated, or otherwise modified from time to time, this “Agreement”), dated as of the 17th of August, 2020 (the “Effective Date”), is entered into by and between Altair Engineering Inc., a Delaware corporation (the “Company”), and Amy Messano (the “Executive”). W I T N E S S E T H: WHEREAS, the Execu

August 17, 2020 EX-10.3

Executive Severance Agreement dated August 17, 2020 between Altair Engineering, Inc. and Dr. Uwe Schramm

EX-10.3 4 d59446dex103.htm EX-10.3 Exhibit 10.3 EXECUTIVE SEVERANCE AGREEMENT THIS EXECUTIVE SEVERANCE AGREEMENT (as amended, restated, or otherwise modified from time to time, this “Agreement”), dated as of the 17th of August, 2020 (the “Effective Date”), is entered into by and between Altair Engineering Inc., a Delaware corporation (the “Company”), and Uwe Schramm (the “Executive”). W I T N E S

August 17, 2020 EX-10.2

Executive Severance Agreement dated August 17, 2020 between Altair Engineering, Inc. and Brett Chouinard

EX-10.2 Exhibit 10.2 EXECUTIVE SEVERANCE AGREEMENT THIS EXECUTIVE SEVERANCE AGREEMENT (as amended, restated, or otherwise modified from time to time, this “Agreement”), dated as of the 17th of August, 2020 (the “Effective Date”), is entered into by and between Altair Engineering Inc., a Delaware corporation (the “Company”), and Brett Chouinard (the “Executive”). W I T N E S S E T H: WHEREAS, the E

August 17, 2020 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 11, 2020 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission

August 6, 2020 EX-99.1

Altair Announces Second Quarter 2020 Financial Results 2020 Second Quarter Revenue Exceeds Guidance Increases Full Year 2020 Outlook

Exhibit 99.1 Altair Announces Second Quarter 2020 Financial Results 2020 Second Quarter Revenue Exceeds Guidance Increases Full Year 2020 Outlook TROY, Mich. – August 6, 2020 – Altair (Nasdaq: ALTR), a global technology company that provides software and cloud solutions in the areas of product development, high performance computing (HPC) and data analytics, today released its financial results fo

August 6, 2020 10-Q

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERING IN

August 6, 2020 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 6, 2020 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission

June 8, 2020 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 2, 2020 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission Fi

June 8, 2020 EX-10.1

Form of 2020 Stock Option Award Agreement.

EX-10.1 Exhibit 10.1 ALTAIR ENGINEERING INC. 2017 EQUITY INCENTIVE PLAN STOCK OPTION AGREEMENT Unless otherwise defined herein, the terms defined in the Altair Engineering Inc. 2017 Equity Incentive Plan (the “Plan”) will have the same defined meanings in this Stock Option Agreement, including the Notice of Stock Option Grant (the “Notice of Grant”), the Terms and Conditions of Stock Option Grant,

May 26, 2020 8-K

Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 19, 2020 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission Fi

May 7, 2020 10-Q

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERING I

May 7, 2020 EX-99.1

Altair Announces First Quarter 2020 Financial Results 2020 First Quarter Software Product Revenue Increased 5% year-over-year

Exhibit 99.1 Altair Announces First Quarter 2020 Financial Results 2020 First Quarter Software Product Revenue Increased 5% year-over-year TROY, Mich. – May 7, 2020 – Altair (Nasdaq: ALTR), a global technology company that provides software and cloud solutions in the areas of product development, high performance computing (HPC) and data analytics, today released its financial results for the firs

May 7, 2020 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 7, 2020 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission Fil

April 15, 2020 CORRESP

-

CORRESP Altair Engineering Inc. 1820 E Big Beaver Road Troy, Michigan 48083 April 15, 2020 Division of Corporation Finance U.S. Securities and Exchange Commission 100 F Street, N.E. Washington, D.C. 20549 Attention: Frank Knapp Christine Dietz Re: Altair Engineering Inc. Form 10-K for the Fiscal Year Ended December 31, 2019 Filed March 2, 2020 File No. 001-38263 Dear Ladies and Gentlemen: This let

April 9, 2020 CORRESP

-

CORRESP April 8, 2020 Division of Corporation Finance U.S. Securities and Exchange Commission 100 F Street, N.E. Washington, D.C. 20549 Attention: Frank Knapp Christine Dietz Re: Altair Engineering Inc. Form 10-K for the Fiscal Year Ended December 31, 2019 Filed March 2, 2020 File No. 001-38263 Dear Ladies and Gentlemen: This letter is submitted by Altair Engineering Inc. (the “Company”) in connec

April 9, 2020 DEFA14A

Altair Engineering Inc. DEFA14A - - DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Definitive Proxy State

April 9, 2020 DEF 14A

Altair Engineering Inc. DEF 14A - - DEF 14A

DEF 14A Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

March 2, 2020 10-K

Annual Report - 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2019 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-38263 ALTAIR ENGINEER

March 2, 2020 S-8

Altair Engineering Inc. S-8 - - S-8

S-8 As filed with the Securities and Exchange Commission on March 2, 2020 Registration No.

March 2, 2020 EX-4.1

Description of Capital Stock

Exhibit 4.1 Description of the Registrant’s Class A Common Stock General The following is a summary of the rights of our Class A common stock. This summary is qualified in its entirety by the provisions of our certificate of incorporation and bylaws, copies of which are filed as exhibits to the Annual Report of which this Exhibit s is a part. Our authorized capital stock consists of 600,000,000 sh

March 2, 2020 EX-21.1

List of Subsidiaries of the Registrant

Exhibit 21.1 LIST OF SUBSIDIARIES Subsidiary Jurisdiction of Organization Altair Product Design, Inc. Michigan, United States Altair Engineering India Pvt. Ltd. India Altair Engineering Ltd. Japan Altair Engineering GmbH Germany Altair Engineering France, Sarl France Altair Engineering Software Co., Ltd. China Altair Engineering Ltd. United Kingdom Datawatch Corporation Delaware, United States Dat

February 27, 2020 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 27, 2020 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissi

February 27, 2020 EX-99.1

Altair Announces Fourth Quarter 2019 Financial Results 2019 Fourth Quarter Software Product Revenue Increased 27% year-over-year

Exhibit 99.1 Altair Announces Fourth Quarter 2019 Financial Results 2019 Fourth Quarter Software Product Revenue Increased 27% year-over-year TROY, Mich. – February 27, 2020 – Altair (Nasdaq:ALTR), a global technology company providing solutions in product development, high-performance computing and data analytics, today released its financial results for the fourth quarter ended December 31, 2019

February 18, 2020 SC 13G/A

021369AA1 / Altair Engr Inc Bond / BAMCO INC /NY/ - NONE Passive Investment

Schedule 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* Altair Engineering Inc. (Name of Issuer) Class A Common Stock (Title of Class of Securities) 021369103 (CUSIP Number) Calendar Year 2019 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule

February 14, 2020 SC 13G

021369AA1 / Altair Engr Inc Bond / Matrix Capital Management Company, LP - ALTAIR ENGINEERING, INC. Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* Altair Engineering, Inc. (Name of Issuer) Class A Common Stock, $0.0001 par value per share (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2019 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule

February 13, 2020 SC 13G/A

021369AA1 / Altair Engr Inc Bond / Neuberger Berman Group LLC - NONE Passive Investment

Schedule 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* Altair Engineering Inc. (Name of Issuer) Common (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2019 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to whi

February 12, 2020 SC 13G/A

021369AA1 / Altair Engr Inc Bond / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 1)* Name of issuer: Altair Engineering Inc Title of Class of Securities: Common Stock CUSIP Number: 021369103 Date of Event Which Requires Filing of this Statement: December 31, 2019 Check the appropriate box to designate the rule pursuant to which this Schedule is filed

February 6, 2020 SC 13G/A

021369AA1 / Altair Engr Inc Bond / Scapa James Ralph - SC 13G/A Passive Investment

SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2019 (Date of Event Which Requires Filing of this Statement) Check the appropriate bo

February 6, 2020 SC 13G/A

021369AA1 / Altair Engr Inc Bond / Christ George J - SC 13G/A Passive Investment

SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* ALTAIR ENGINEERING INC. (Name of Issuer) CLASS A COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2019 (Date of Event Which Requires Filing of this Statement) Check the appropriate bo

January 17, 2020 SC 13G

021369AA1 / Altair Engr Inc Bond / Conestoga Capital Advisors, LLC - CONESTOGA CAPITAL ADVISORS Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 ALTAIR ENGINEERING, INC. (Name of Issuer) (Class A) Common Stock, $0.01 Par Value (Title of Class of Securities) 021369103 (CUSIP Number) December 31, 2019 (Date of Event which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to w

November 7, 2019 EX-99

Altair Announces Third Quarter 2019 Financial Results 2019 Third Quarter Software Product Revenue Increased 21% year-over-year

EX-99 2 altr-ex996.htm EX-99 Exhibit 99.1 Altair Announces Third Quarter 2019 Financial Results 2019 Third Quarter Software Product Revenue Increased 21% year-over-year TROY, Mich. – November 7, 2019 – Altair (Nasdaq:ALTR), a global technology company providing solutions in product development, high-performance computing and data intelligence, today released its financial results for the third qua

November 7, 2019 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 7, 2019 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commissio

November 7, 2019 10-Q

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERI

October 10, 2019 8-K

Unregistered Sales of Equity Securities

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 7, 2019 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission

August 8, 2019 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 8, 2019 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Commission

August 8, 2019 EX-99.1

Altair Announces Second Quarter 2019 Financial Results 2019 Second Quarter Software Product Revenue Increased 20% year-over-year

Exhibit 99.1 Altair Announces Second Quarter 2019 Financial Results 2019 Second Quarter Software Product Revenue Increased 20% year-over-year TROY, Mich. – August 8, 2019 – Altair (Nasdaq:ALTR), a global technology company providing solutions in product development, high-performance computing and data intelligence, today released its financial results for the second quarter ended June 30, 2019. “W

August 8, 2019 10-Q

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38263 ALTAIR ENGINEERING IN

June 14, 2019 EX-99.1

Altair Announces Sale of $230 Million Aggregate Principal Amount of Convertible Senior Notes

EX-99.1 2 d765558dex991.htm EX-99.1 Exhibit 99.1 Altair Announces Sale of $230 Million Aggregate Principal Amount of Convertible Senior Notes TROY, Mich. – June 14, 2019 (GLOBE NEWSWIRE) – Altair Engineering Inc. (Nasdaq: ALTR) (“Altair”) today announced the closing of its public offering of convertible senior notes and the exercise in full of the underwriters’ option to purchase additional conver

June 14, 2019 8-K

Financial Statements and Exhibits, Other Events

Form 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 14, 2019 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Com

June 10, 2019 EX-4.1

Indenture, dated as of June 10, 2019, by and between Altair Engineering Inc. and U.S. Bank National Association.

EX-4.1 Exhibit 4.1 ALTAIR ENGINEERING INC., Issuer AND U.S. BANK NATIONAL ASSOCIATION, Trustee INDENTURE Dated as of June 10, 2019 Senior Debt Securities TABLE OF CONTENTS1 ARTICLE 1 DEFINITIONS 1 Section 1.01 Definitions of Terms 1 ARTICLE 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES 5 Section 2.01 Designation and Terms of Securities 5 Section 2.02 Form of Secur

June 10, 2019 EX-4.2

First Supplemental Indenture, dated as of June 10, 2019, by and between Altair Engineering Inc. and U.S. Bank National Association.

EX-4.2 3 d760947dex42.htm EX-4.2 Exhibit 4.2 ALTAIR ENGINEERING INC. AND U.S. BANK NATIONAL ASSOCIATION, as Trustee FIRST SUPPLEMENTAL INDENTURE Dated as of June 10, 2019 to Indenture Dated as of June 10, 2019 0.250% Convertible Senior Notes due 2024 TABLE OF CONTENTS PAGE ARTICLE 1 DEFINITIONS Section 1.01. Definitions 2 Section 1.02. References to Interest 13 ARTICLE 2 ISSUE, DESCRIPTION, EXECUT

June 10, 2019 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant, Other Events

Form 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 10, 2019 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Com

June 6, 2019 424B5

CALCULATION OF REGISTRATION FEE Title of Each Class of Securities to be Registered Amount To Be Registered Maximum Offering Price per Unit Maximum Aggregate Offering Price(2) Amount of Registration Fee(2) 0.250% Convertible Senior Notes due 2024 $230

424B5 Table of Contents Filed Pursuant to Rule 424(b)(5) Registration No. 333-231948 CALCULATION OF REGISTRATION FEE Title of Each Class of Securities to be Registered Amount To Be Registered Maximum Offering Price per Unit Maximum Aggregate Offering Price(2) Amount of Registration Fee(2) 0.250% Convertible Senior Notes due 2024 $230,000,000(1) 100% $230,000,000 $27,876 Class A Common Stock, $0.00

June 6, 2019 EX-1.1

Note Underwriting Agreement, dated as of June 5, 2019, by and between Altair Engineering Inc., and J.P. Morgan Securities LLC, as representative of the underwriters.

EX-1.1 Exhibit 1.1 ALTAIR ENGINEERING INC. 0.250% Convertible Senior Notes due June 1, 2024 Underwriting Agreement June 5, 2019 J. P. Morgan Securities LLC As Representative of the several Underwriters listed in Schedule 1 hereto c/o J. P. Morgan Securities LLC 383 Madison Avenue New York, New York 10179 Ladies and Gentlemen: Altair Engineering Inc., a Delaware corporation (the “Company”), propose

June 6, 2019 EX-10.1

Second Amendment to the Company’s Third Amended and Restated Credit Agreement, by and among the Company, as borrower, the lenders party thereto, and JPMorgan Chase Bank, N.A., as Administrative Agent.

EX-10.1 4 d756232dex101.htm EX-10.1 Exhibit 10.1 SECOND AMENDMENT TO THIRD AMENDED AND RESTATED CREDIT AGREEMENT This Second Amendment to Third Amended and Restated Credit Agreement, dated as of June 5, 2019 (this “Amendment”), is among Altair Engineering Inc. (the “Borrower”), the Lenders party hereto, and JPMorgan Chase Bank, N.A., as Administrative Agent (in such capacity, the “Administrative A

June 6, 2019 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

Form 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 5, 2019 Altair Engineering Inc. (Exact name of registrant as specified in its charter) Delaware 001-38263 38-2591828 (State or other jurisdiction of incorporation) (Comm

June 6, 2019 FWP

PRICING TERM SHEET June 5, 2019 Altair Engineering Inc. $200,000,000 Aggregate Principal Amount of 0.250% Convertible Senior Notes due 2024 (the “Offering”)

FWP Free Writing Prospectus Filed pursuant to Rule 433 Relating to the Preliminary Prospectus Supplement dated June 4, 2019 to the Prospectus dated June 4, 2019 Registration No.

June 4, 2019 424B5

Altair Engineering Inc. 1820 E. Big Beaver Road Troy, Michigan 48083 (248) 614-2400 Attention: General Counsel

424B5 Table of Contents Filed Pursuant to Rule 424(b)(5) Registration No. 333-231948 The information in this preliminary prospectus supplement is not complete and may be changed. A registration statement relating to the securities has become effective under the Securities Act of 1933, as amended. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell the se

June 4, 2019 EX-4.4

Form of Indenture.

EX-4.4 Exhibit 4.4 ALTAIR ENGINEERING INC., Issuer AND U.S. BANK NATIONAL ASSOCIATION, Trustee INDENTURE Dated as of [ ], 201[ ] Senior Debt Securities TABLE OF CONTENTS1 ARTICLE 1 DEFINITIONS 1 Section 1.01 Definitions of Terms 1 ARTICLE 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES 5 Section 2.01 Designation and Terms of Securities 5 Section 2.02 Form of Securit

June 4, 2019 EX-25.1

Statement of Eligibility of Trustee under the Senior Indenture.

EX-25.1 Exhibit 25.1 SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE ☐ Check if an Application to Determine Eligibility of a Trustee Pursuant to Section 305(b)(2) U.S. BANK NATIONAL ASSOCIATION (Exact name of Trustee as specified in its charter) 31-0841368 I.R.S. Employer

June 4, 2019 S-3ASR

Altair Engineering Inc. S-3ASR - - S-3ASR

S-3ASR Table of Contents As filed with the Securities and Exchange Commission on June 4, 2019 Registration No.

June 4, 2019 EX-99.1

UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS

EX-99.1 EXHIBIT 99.1 UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS On November 5, 2018, Altair Engineering Inc. (“Altair” or the “Company”) entered into an Agreement and Plan of Merger (the “Merger Agreement”), by and among Altair, Dallas Merger Sub, Inc., a Delaware corporation and a wholly-owned indirect subsidiary of Altair (“Purchaser”), and Datawatch Corporation (“Datawatch”). I

Fintel data has been cited in the following publications:
Daily Mail Fox Business Business Insider Wall Street Journal The Washington Post Bloomberg Financial Times Globe and Mail
NASDAQ.com Reuters The Guardian Associated Press FactCheck.org Snopes Politifact
Federal Register The Intercept Forbes Fortune Magazine TheStreet Time Magazine Canadian Broadcasting Corporation International Business Times
Cambridge University Press Investopedia MarketWatch NY Daily News Entrepreneur Newsweek Barron's El Economista