Stephanie Buckner - 26 Mar 2025 Form 4 Insider Report for Altair Engineering Inc. (ALTR)

Footnote F1

On March 26, 2025, the Company was acquired by Siemens Industry Software Inc. ("Siemens") pursuant to the merger agreement entered into among the Company, Siemens, and Astra Merger Sub Inc., dated as of October 30, 2024.

Footnote F2

Includes 0 Class A Common Stock restricted stock units ("RSUs") that are unvested and scheduled to vest on or prior to December 31, 2025, and 17,141 RSUs that are unvested and scheduled to vest on or after January 1, 2026.

Footnote F3

Upon the consummation of the merger, each issued and outstanding share of the Company's Class A Common Stock ("Common Stock") was canceled and converted into the right receive $113.00 in cash without interest. Each RSU that was granted under the Company's 2017 Equity Incentive Plan (the "2017 Plan") that was outstanding immediately prior to the consummation of the merger and was scheduled to vest on or before December 31, 2025 was vested, canceled and converted into the right to receive $113.00 in cash without interest.

Footnote F4

(continued from footnote 3) Each RSU that was granted under the 2017 Plan that was outstanding immediately prior to the consummation of the merger, and scheduled to vest on or after January 1, 2026 was canceled and converted into the right to receive $113.00 in cash without interest, and will be paid on the last day of the calendar quarter preceding the quarter in which such RSU would have otherwise vested in accordance with the vesting schedule in effect immediately prior to the consummation of the merger, less any applicable withholding taxes, subject to acceleration in certain circumstances.

Footnote F5

Includes 478 Class A Common Stock restricted stock units ("RSUs") that are unvested and scheduled to vest on or prior to December 31, 2025, and 1,074 RSUs that are unvested and scheduled to vest on or after January 1, 2026.

Footnote F6

This option is fully vested.

Footnote F7

Each option that was outstanding immediately prior to the consummation of the merger and was scheduled to vest on or before December 31, 2025 was vested, canceled and converted into the right to receive the cash value of the option. Each option that was outstanding immediately prior to the consummation of the merger, and scheduled to vest on or after January 1, 2026 was canceled and converted into a right to receive the cash value of the option, such cash value of the option to be paid on the last day of the calendar quarter preceding the quarter in which such option would have otherwise vested in accordance with the vesting schedule in effect immediately prior to the consummation of the merger, less any applicable withholding taxes, subject to acceleration in certain circumstances.

Footnote F8

This option represents an aggregate cash value of $32,346.00, representing the difference between the exercise price of the option and $113.00.

Footnote F9

This option is fully vested.

Footnote F10

This option represents an aggregate cash value of $77,464.75, representing the difference between the exercise price of the option and $113.00.

Footnote F11

This option is fully vested.

Footnote F12

This option represents an aggregate cash value of $1,514,826.00, representing the difference between the exercise price of the option and $113.00.

Footnote F13

This option is fully vested.

Footnote F14

This option represents an aggregate cash value of $1,371,825.00, representing the difference between the exercise price of the option and $113.00.

Footnote F15

This option is fully vested.

Footnote F16

This option represents an aggregate cash value of $320,719.60, representing the difference between the exercise price of the option and $113.00.

Footnote F17

Includes 0 shares of Common Stock underlying the options that are unvested and scheduled to vest on or prior to December 31, 2025, and 1,500 shares of Common Stock underlying the options that are unvested and scheduled to vest on or after January 1, 2026.

Footnote F18

This option represents an aggregate cash value of $307,260.00, representing the difference between the exercise price of the option and $113.00.

Footnote F19

Includes 12,000 shares of Common Stock underlying the options that are unvested and scheduled to vest on or prior to December 31, 2025, and 0 shares of Common Stock underlying the options that are unvested and scheduled to vest on or after January 1, 2026.

Footnote F20

This option represents an aggregate cash value of $1,610,160.00, representing the difference between the exercise price of the option and $113.00.

Footnote F21

Includes 0 shares of Common Stock underlying the options that are unvested and scheduled to vest on or prior to December 31, 2025, and 6,250 shares of Common Stock underlying the options that are unvested and scheduled to vest on or after January 1, 2026.

Footnote F22

This option represents an aggregate cash value of $597,625.00, representing the difference between the exercise price of the option and $113.00.

Footnote F23

Includes 0 shares of Common Stock underlying the options that are unvested and scheduled to vest on or prior to December 31, 2025, and 10,547 shares of Common Stock underlying the options that are unvested and scheduled to vest on or after January 1, 2026.

Footnote F24

This option represents an aggregate cash value of $477,720.11, representing the difference between the exercise price of the option and $113.00.

Footnote F25

This option is fully vested.

Footnote F26

This option represents an aggregate cash value of $439,080.00, representing the difference between the exercise price of the option and $113.00.

Footnote F27

This option is fully vested.

Footnote F28

This option represents an aggregate cash value of $365,820.00, representing the difference between the exercise price of the option and $113.00.

Footnote F29

Includes 1,071 shares of Common Stock underlying the options that are unvested and scheduled to vest on or prior to December 31, 2025, and 0 shares of Common Stock underlying the options that are unvested and scheduled to vest on or after January 1, 2026.

Footnote F30

This option represents an aggregate cash value of $141,180.84, representing the difference between the exercise price of the option and $113.00.

Footnote F31

Includes 364 shares of Common Stock underlying the options that are unvested and scheduled to vest on or prior to December 31, 2025, and 364 shares of Common Stock underlying the options that are unvested and scheduled to vest on or after January 1, 2026.

Footnote F32

This option represents an aggregate cash value of $91,630.73, representing the difference between the exercise price of the option and $113.00.

Footnote F33

Includes 4,000 shares of Common Stock underlying the options that are unvested and scheduled to vest on or prior to December 31, 2025, and 0 shares of Common Stock underlying the options that are unvested and scheduled to vest on or after January 1, 2026.

Footnote F34

This option represents an aggregate cash value of $536,720.00, representing the difference between the exercise price of the option and $113.00.

Footnote F35

Includes 0 shares of Common Stock underlying the options that are unvested and scheduled to vest on or prior to December 31, 2025, and 890 shares of Common Stock underlying the options that are unvested and scheduled to vest on or after January 1, 2026.

Footnote F36

This option represents an aggregate cash value of $85,101.80, representing the difference between the exercise price of the option and $113.00.