OS · OneStream, Inc.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each vested option was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR Americas XII EEA (Dream) Blocker Parent L.P.

KKR Associates Americas XII AIV L.P. is the general partner of each of KKR Americas Fund XII (Dream) L.P., KKR Americas XII (Dream) Blocker Parent L.P., KKR Americas XII EEA (Dream) Blocker Parent L.P., and KKR Americas XII (Dream II) Blocker Parent L.P. KKR Americas XII AIV GP LLC is the general partner of KKR Associates Americas XII AIV L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Common Units represented limited liability company units of Company LLC and an equal number of shares of Class C Common Stock of the Issuer. Common Units were redeemable by the holder at any time on or following the closing of the Issuer's initial public offering for shares of Class D Common Stock of the Issuer on a one-for-one basis, and a corresponding number of shares of Class C Common Stock would be forfeited in connection with the redemption. At the Effective Time, each Common Unit was cancelled and converted into the right to receive an amount in cash, without interest, equal to the Per Share Price. Each corresponding share of Class C Common Stock was cancelled and converted into the right to receive $0.0001 in cash, without interest.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR Dream Holdings LLC. KKR Dream Aggregator L.P. is the sole member of KKR Dream Holdings LLC. KKR Dream Aggregator GP LLC is the general partner of KKR Dream Aggregator L.P. KKR Americas Fund XII (Dream) L.P. is the sole member of KKR Dream Aggregator GP LLC.

KKR Associates Americas XII AIV L.P. is the general partner of each of KKR Americas Fund XII (Dream) L.P., KKR Americas XII (Dream) Blocker Parent L.P., KKR Americas XII EEA (Dream) Blocker Parent L.P., and KKR Americas XII (Dream II) Blocker Parent L.P. KKR Americas XII AIV GP LLC is the general partner of KKR Associates Americas XII AIV L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

At the Effective Time, each Common Unit was cancelled and converted into the right to receive an amount in cash, without interest, equal to the Per Share Price, less applicable withholding taxes. Each corresponding share of Class C Common Stock was cancelled and converted into the right to receive $0.0001 in cash, without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Shares held of record by the TSICU Corp. TSICU Corp. is a subchapter S corporation controlled by the Reporting Person, who has sole voting and dispositive power over the shares held by it.

Common Units represented limited liability company units of Company LLC and an equal number of shares of Class C Common Stock of the Issuer. Common Units were redeemable by the holder at any time on or following the closing of the Issuer's initial public offering for shares of Class D Common Stock of the Issuer on a one-for-one basis, and a corresponding number of shares of Class C Common Stock would be forfeited in connection with the redemption. At the Effective Time, each Common Unit was cancelled and converted into the right to receive an amount in cash, without interest, equal to the Per Share Price. Each corresponding share of Class C Common Stock was cancelled and converted into the right to receive $0.0001 in cash, without interest.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR Dream Holdings LLC. KKR Dream Aggregator L.P. is the sole member of KKR Dream Holdings LLC. KKR Dream Aggregator GP LLC is the general partner of KKR Dream Aggregator L.P. KKR Americas Fund XII (Dream) L.P. is the sole member of KKR Dream Aggregator GP LLC.

KKR Associates Americas XII AIV L.P. is the general partner of each of KKR Americas Fund XII (Dream) L.P., KKR Americas XII (Dream) Blocker Parent L.P., KKR Americas XII EEA (Dream) Blocker Parent L.P., and KKR Americas XII (Dream II) Blocker Parent L.P. KKR Americas XII AIV GP LLC is the general partner of KKR Associates Americas XII AIV L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR NGT (Dream) Blocker Parent (EEA) L.P.

KKR Associates NGT L.P. is the general partner of KKR NGT (Dream) Blocker Parent L.P. and KKR NGT (Dream) Blocker Parent (EEA) L.P. KKR Next Gen Tech Growth Limited is the general partner of KKR Associates NGT L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR-Milton Strategic Partners L.P. KKR Associates Milton Strategic L.P. is the general partner of KKR-Milton Strategic Partners L.P. KKR Milton Strategic Limited is the general partner of KKR Associates Milton Strategic L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR-Milton Strategic Partners L.P. KKR Associates Milton Strategic L.P. is the general partner of KKR-Milton Strategic Partners L.P. KKR Milton Strategic Limited is the general partner of KKR Associates Milton Strategic L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each vested option was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of the option, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Pursuant to the Merger Agreement, at the effective time of the Mergers (the "Effective Time"), each share of Issuer Class A Common Stock was canceled and converted into the right to receive $24.00 per share in cash (the "Per Share Price"), without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each unvested option was cancelled and converted into the contingent right to receive a cash award, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of the option, less applicable withholding taxes. The vesting terms and conditions applicable to the unvested option as of immediately prior to the Mergers will remain in effect following the Mergers.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each unvested option was cancelled and converted into the contingent right to receive a cash award, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes. The vesting terms and conditions applicable to the unvested option as of immediately prior to the Mergers will remain in effect following the Mergers.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Pursuant to Issuer's outside director compensation policy, immediately prior to the Effective Time, the shares subject to the option became fully vested and immediately exercisable. At the Effective Time, the option was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes.

At the Effective Time, each Common Unit was cancelled and converted into the right to receive an amount in cash, without interest, equal to the Per Share Price, less applicable withholding taxes. Each corresponding share of Class C Common Stock was cancelled and converted into the right to receive $0.0001 in cash, without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents an equal number of restricted stock units ("RSUs"). Pursuant to Issuer's outside director compensation policy, immediately before the Effective Time, each RSU award held by a non-employee director that was outstanding and unvested as of immediately before the Effective Time (a "Director RSU Award") accelerated and became fully vested. At the Effective Time, each Director RSU Award was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) the Per Share Price multiplied by (b) the total number of shares of Issuer's Class A Common Stock covered by such Director RSU Award, less applicable withholding taxes.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR Americas XII (Dream) Blocker Parent L.P.

KKR Associates Americas XII AIV L.P. is the general partner of each of KKR Americas Fund XII (Dream) L.P., KKR Americas XII (Dream) Blocker Parent L.P., KKR Americas XII EEA (Dream) Blocker Parent L.P., and KKR Americas XII (Dream II) Blocker Parent L.P. KKR Americas XII AIV GP LLC is the general partner of KKR Associates Americas XII AIV L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each unvested option was cancelled and converted into the contingent right to receive a cash award, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of the option, less applicable withholding taxes. The vesting terms and conditions applicable to the unvested option as of immediately prior to the Mergers will remain in effect following the Mergers.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR NGT (Dream) Blocker Parent (EEA) L.P.

KKR Associates NGT L.P. is the general partner of KKR NGT (Dream) Blocker Parent L.P. and KKR NGT (Dream) Blocker Parent (EEA) L.P. KKR Next Gen Tech Growth Limited is the general partner of KKR Associates NGT L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR Americas XII EEA (Dream) Blocker Parent L.P.

KKR Associates Americas XII AIV L.P. is the general partner of each of KKR Americas Fund XII (Dream) L.P., KKR Americas XII (Dream) Blocker Parent L.P., KKR Americas XII EEA (Dream) Blocker Parent L.P., and KKR Americas XII (Dream II) Blocker Parent L.P. KKR Americas XII AIV GP LLC is the general partner of KKR Associates Americas XII AIV L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents an equal number of restricted stock units ("RSUs"). At the Effective Time, each unvested RSU award was cancelled and converted into the contingent right to receive a cash award, without interest, equal to the product of (a) the Per Share Price multiplied by (b) the total number of shares of Issuer's Class A Common Stock covered by such RSU award, less applicable withholding taxes. The vesting terms and conditions applicable to the unvested RSU awards as of immediately prior to the Mergers will remain in effect following the Mergers, provided that the vesting and payment of these cash awards to the extent not yet paid will accelerate and be paid upon the earlier of March 15, 2027 or a termination or resignation of the Reporting Person's employment with the Issuer, as a privately held entity, following the Mergers for any reason other than for cause.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR Americas XII EEA (Dream) Blocker Parent L.P.

KKR Associates Americas XII AIV L.P. is the general partner of each of KKR Americas Fund XII (Dream) L.P., KKR Americas XII (Dream) Blocker Parent L.P., KKR Americas XII EEA (Dream) Blocker Parent L.P., and KKR Americas XII (Dream II) Blocker Parent L.P. KKR Americas XII AIV GP LLC is the general partner of KKR Associates Americas XII AIV L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR-Milton Strategic Partners L.P. KKR Associates Milton Strategic L.P. is the general partner of KKR-Milton Strategic Partners L.P. KKR Milton Strategic Limited is the general partner of KKR Associates Milton Strategic L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents an equal number of restricted stock units ("RSUs"). Pursuant to Issuer's outside director compensation policy, immediately before the effective time of the Mergers (the "Effective Time"), each RSU award held by a non-employee director that was outstanding and unvested as of immediately before the Effective Time (a "Director RSU Award") accelerated and became fully vested. At the Effective Time, each Director RSU Award was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) $24.00 (the "Per Share Price") multiplied by (b) the total number of shares of Issuer's Class A Common Stock covered by such Director RSU Award, less applicable withholding taxes.

Common Units represented limited liability company units of Company LLC and an equal number of shares of Class C Common Stock of the Issuer. Common Units were redeemable by the holder at any time on or following the closing of the Issuer's initial public offering for shares of Class D Common Stock of the Issuer on a one-for-one basis, and a corresponding number of shares of Class C Common Stock would be forfeited in connection with the redemption. At the Effective Time, each Common Unit was cancelled and converted into the right to receive an amount in cash, without interest, equal to the Per Share Price. Each corresponding share of Class C Common Stock was cancelled and converted into the right to receive $0.0001 in cash, without interest.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR Dream Holdings LLC. KKR Dream Aggregator L.P. is the sole member of KKR Dream Holdings LLC. KKR Dream Aggregator GP LLC is the general partner of KKR Dream Aggregator L.P. KKR Americas Fund XII (Dream) L.P. is the sole member of KKR Dream Aggregator GP LLC.

KKR Associates Americas XII AIV L.P. is the general partner of each of KKR Americas Fund XII (Dream) L.P., KKR Americas XII (Dream) Blocker Parent L.P., KKR Americas XII EEA (Dream) Blocker Parent L.P., and KKR Americas XII (Dream II) Blocker Parent L.P. KKR Americas XII AIV GP LLC is the general partner of KKR Associates Americas XII AIV L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR NGT (Dream) Blocker Parent (EEA) L.P.

KKR Associates NGT L.P. is the general partner of KKR NGT (Dream) Blocker Parent L.P. and KKR NGT (Dream) Blocker Parent (EEA) L.P. KKR Next Gen Tech Growth Limited is the general partner of KKR Associates NGT L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Pursuant to Issuer's outside director compensation policy, immediately prior to the Effective Time, the shares subject to the option became fully vested and immediately exercisable. At the Effective Time, the option was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each vested option was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each unvested option was cancelled and converted into the contingent right to receive a cash award, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of the option, less applicable withholding taxes. The vesting terms and conditions applicable to the unvested option as of immediately prior to the Mergers will remain in effect following the Mergers.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents an equal number of restricted stock units ("RSUs"). Pursuant to Issuer's outside director compensation policy, immediately before the effective time of the Mergers (the "Effective Time"), each RSU award held by a non-employee director that was outstanding and unvested as of immediately before the Effective Time (a "Director RSU Award") accelerated and became fully vested. At the Effective Time, each Director RSU Award was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) $24.00 (the "Per Share Price") multiplied by (b) the total number of shares of Issuer's Class A Common Stock covered by such Director RSU Award, less applicable withholding taxes.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR Custom Equity Opportunities Fund L.P. KKR Associates Custom Equity Opportunities L.P. is the general partner of KKR Custom Equity Opportunities Fund L.P. KKR Custom Equity Opportunities Limited is the general partner of KKR Associates Custom Equity Opportunities L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR TFO Partners L.P. KKR Associates TFO L.P. is the general partner of KKR TFO Partners L.P. KKR TFO GP Limited is the general partner of KKR Associates TFO L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each vested option was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR Americas XII (Dream) Blocker Parent L.P.

KKR Associates Americas XII AIV L.P. is the general partner of each of KKR Americas Fund XII (Dream) L.P., KKR Americas XII (Dream) Blocker Parent L.P., KKR Americas XII EEA (Dream) Blocker Parent L.P., and KKR Americas XII (Dream II) Blocker Parent L.P. KKR Americas XII AIV GP LLC is the general partner of KKR Associates Americas XII AIV L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Pursuant to Issuer's outside director compensation policy, immediately prior to the Effective Time, the shares subject to the option became fully vested and immediately exercisable. At the Effective Time, the option was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes.

At the Effective Time, each Common Unit was cancelled and converted into the right to receive an amount in cash, without interest, equal to the Per Share Price, less applicable withholding taxes. Each corresponding share of Class C Common Stock was cancelled and converted into the right to receive $0.0001 in cash, without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

The Reporting Person may be deemed to have voting and dispositive power over the shares held by CaitRyan LLC and the Hohenstein Purple Elephant 2019 Irrevocable Grantor Trust.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR Custom Equity Opportunities Fund L.P. KKR Associates Custom Equity Opportunities L.P. is the general partner of KKR Custom Equity Opportunities Fund L.P. KKR Custom Equity Opportunities Limited is the general partner of KKR Associates Custom Equity Opportunities L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR NGT (Dream) Blocker Parent L.P.

KKR Associates NGT L.P. is the general partner of KKR NGT (Dream) Blocker Parent L.P. and KKR NGT (Dream) Blocker Parent (EEA) L.P. KKR Next Gen Tech Growth Limited is the general partner of KKR Associates NGT L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR Americas XII (Dream II) Blocker Parent L.P.

KKR Associates Americas XII AIV L.P. is the general partner of each of KKR Americas Fund XII (Dream) L.P., KKR Americas XII (Dream) Blocker Parent L.P., KKR Americas XII EEA (Dream) Blocker Parent L.P., and KKR Americas XII (Dream II) Blocker Parent L.P. KKR Americas XII AIV GP LLC is the general partner of KKR Associates Americas XII AIV L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each unvested option was cancelled and converted into the contingent right to receive a cash award, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes. The vesting terms and conditions applicable to the unvested option as of immediately prior to the Mergers will remain in effect following the Mergers.

Pursuant to the Merger Agreement, at the Effective Time, each share of Class D Common Stock was cancelled and converted into the right to receive the Per Share Price, without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Shares held of record by the Shea Family Trust dated December 25, 2019 (the "2019 Shea Family Trust"). The Reporting Person's spouse serves as the co-trustee for the 2019 Shea Family Trust. By virtue of his relationship, the Reporting Person may be deemed to share voting and dispositive power with respect to the shares held by the 2019 Shea Family Trust.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each unvested option was cancelled and converted into the contingent right to receive a cash award, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes. The vesting terms and conditions applicable to the unvested option as of immediately prior to the Mergers will remain in effect following the Mergers.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents an equal number of restricted stock units ("RSUs"). At the Effective Time, each unvested RSU award was cancelled and converted into the contingent right to receive a cash award, without interest, equal to the product of (a) the Per Share Price multiplied by (b) the total number of shares of Issuer's Class A Common Stock covered by such RSU award, less applicable withholding taxes. The vesting terms and conditions applicable to the unvested RSU awards as of immediately prior to the Mergers will remain in effect following the Mergers.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR Americas XII (Dream) Blocker Parent L.P.

KKR Associates Americas XII AIV L.P. is the general partner of each of KKR Americas Fund XII (Dream) L.P., KKR Americas XII (Dream) Blocker Parent L.P., KKR Americas XII EEA (Dream) Blocker Parent L.P., and KKR Americas XII (Dream II) Blocker Parent L.P. KKR Americas XII AIV GP LLC is the general partner of KKR Associates Americas XII AIV L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each unvested option was cancelled and converted into the contingent right to receive a cash award, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes. The vesting terms and conditions applicable to the unvested option as of immediately prior to the Mergers will remain in effect following the Mergers, provided that the vesting and payment of these cash awards to the extent not yet paid will accelerate and be paid upon the earlier of March 15, 2027 or a termination or resignation of the Reporting Person's employment with the Issuer, as a privately held entity, following the Mergers for any reason other than for cause.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each vested option was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of the option, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Pursuant to the Merger Agreement, at the effective time of the Mergers (the "Effective Time"), each share of Issuer Class A Common Stock was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price"), without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each vested option was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes.

At the Effective Time, the shares of Class D Common Stock were reinvested into Issuer, as a privately held entity following the Mergers, and were exchanged for equity interests in an entity that controls Parent.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Shares held of record by the Shea Family Trust dated December 25, 2019 (the "2019 Shea Family Trust"). The Reporting Person's spouse serves as the co-trustee for the 2019 Shea Family Trust. By virtue of his relationship, the Reporting Person may be deemed to share voting and dispositive power with respect to the shares held by the 2019 Shea Family Trust.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

At the Effective Time, each vested option was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes.

Pursuant to the Merger Agreement, immediately before the effective time of the Mergers (the "Effective Time"), each share of Class D Common Stock of the Issuer was cancelled and converted into the right to receive $24.00 per share in cash (the "Per Share Price") without interest, less applicable withholding taxes.

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Represents securities held by KKR TFO Partners L.P. KKR Associates TFO L.P. is the general partner of KKR TFO Partners L.P. KKR TFO GP Limited is the general partner of KKR Associates TFO L.P.

KKR Group Partnership L.P. is the sole member of each of KKR Americas XII AIV GP LLC, KKR Holdco LLC, and KKR Associates Group GP LLC and sole shareholder of each of KKR TFO GP Limited, KKR Custom Equity Opportunities Limited, KKR Milton Strategic Limited and KKR Next Gen Tech Growth Limited. KKR Group Holdings Corp. is the general partner of KKR Group Partnership L.P. KKR Group Co. Inc. is the sole shareholder of KKR Group Holdings Corp. KKR & Co. Inc. is the sole shareholder of KKR Group Co. Inc. KKR Management LLP is the Series I preferred stockholder of KKR & Co. Inc. Messrs. Henry R. Kravis and George R. Roberts are the founding partners of KKR Management LLP.

Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons were the beneficial owners of any securities reported herein.