LFST · LifeStance Health Group, Inc.

Includes 45,495 restricted stock units ("RSUs"). Each RSU represents a contingent right to receive one share of the Issuer's common stock.

Includes 17,746 restricted stock units ("RSUs"). Each RSU represents a contingent right to receive one share of the Issuer's common stock.

Includes 17,746 restricted stock units ("RSUs"). Each RSU represents a contingent right to receive one share of the Issuer's common stock.

Includes 35,492 restricted stock units ("RSUs"). Each RSU represents a contingent right to receive one share of the Issuer's common stock.

Includes 17,746 restricted stock units ("RSUs"). Each RSU represents a contingent right to receive one share of the Issuer's common stock.

Includes 17,746 restricted stock units ("RSUs"). Each RSU represents a contingent right to receive one share of the Issuer's common stock.

Includes 35,492 restricted stock units ("RSUs"). Each RSU represents a contingent right to receive one share of the Issuer's common stock.

The price reported is a weighted average price. These shares were sold in multiple transactions ranging from $10.00 to $10.295 inclusive. The Reporting Person undertakes to provide to the Company, any security holder of the Company or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of the Exchange Act of 1934 (the "Exchange Act") or for any other purpose.

The price reported is a weighted average price. These shares were sold in multiple transactions ranging from $10.00 to $10.295 inclusive. The Reporting Person undertakes to provide to the Company, any security holder of the Company or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of the Exchange Act or for any other purpose.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of restricted stock units ("RSUs") that vested on June 11, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested RSUs and do not constitute any open-market sale.

The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of the Exchange Act or for any other purpose.

Each of James G. Coulter and Jon Winkelried own entities that control TPG GP A, LLC (together with Messrs. Coulter and Winkelried, the "Reporting Persons"), which exercises direct or indirect control over entities that collectively hold 100% of the shares of Class B common stock (which represents a majority of the combined voting power of the common stock) of TPG Inc., which is the sole member of TPG GPCo, LLC, which is the sole member of TPG Holdings II-A, LLC, which is the general partner of TPG Operating Group II, L.P., which is the sole member of TPG Holdings I-A, LLC, which is the general partner of TPG Operating Group I, L.P., which is the sole member of TPG GenPar VIII Advisors, LLC, which is the general partner of TPG GenPar VIII, L.P., which is the general partner of TPG VIII Lynnwood Holdings Aggregation, L.P. ("TPG VIII Lynnwood"), which directly holds 111,744,614 shares of Common Stock of LifeStance Health Group, Inc.

Because of the relationship between the Reporting Persons and TPG VIII Lynnwood, the Reporting Persons may be deemed to beneficially own the securities reported herein to the extent of the greater of their respective direct or indirect pecuniary interests in the profits or capital accounts of TPG VIII Lynnwood. Each of TPG VIII Lynnwood and each Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of TPG VIII Lynnwood's or such Reporting Person's pecuniary interest therein, if any.

Pursuant to Rule 16a-1(a)(4) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests.

Represents 3,612,708 shares sold by Summit Partners Growth Equity Fund IX-A, L.P., 2,255,726 shares sold by Summit Partners Growth Equity Fund IX-B, L.P., 25,218 shares sold by Summit Investors GE IX/VC IV, LLC, 3,371 shares sold by Summit Partners Entrepreneur Advisors Fund II, L.P. and 2,638 shares sold by Summit Investors GE IX/VC IV (UK), L.P.

The reported securities are held as follows: 14,274,150 shares in the name of Summit Partners Growth Equity Fund IX-A, L.P.; 8,912,582 shares in the name of Summit Partners Growth Equity Fund IX-B, L.P.; 99,639 shares in the name of Summit Investors GE IX/VC IV, LLC; 13,320 shares in the name of Summit Partners Entrepreneur Advisors Fund II, L.P.; and 10,424 shares in the name of Summit Investors GE IX/ VC IV (UK), L.P.

Darren Black is a Managing Director and Member of Summit Master Company, LLC, the general partner of Summit Partners, L.P. Summit Partners, L.P. is the managing member of Summit Partners GE IX, LLC, which is general partner of Summit Partners GE IX, LP, which is the general partner of Summit Partners Growth Equity Fund IX-A, L.P. and Summit Partners Growth Equity Fund IX-B, L.P. Summit Master Company, LLC is (i) the sole member of Summit Partners Entrepreneur Advisors GP II, LLC, which is the general partner of Summit Partners Entrepreneur Advisors Fund II, L.P. and (ii) the managing member of Summit Investors Management, LLC, which is the manager of Summit Investors GE IX/VC IV, LLC, and the general partner of Summit Investors GE IX/VC IV (UK), L.P.

Summit Master Company, LLC, as the sole member of Summit Partners Entrepreneur Advisors GP II, LLC and the managing member of Summit Investors Management, LLC, has delegated investment decisions, including voting and dispositive power, to Summit Partners, L.P. and its investment committee responsible for voting and investment decisions with respect to LifeStance Health Group, Inc. Summit Partners, L.P., through a three person investment committee, currently composed of Peter Y. Chung, Darren M. Black and Craig D. Frances, has voting and dispositive authority over the shares held by each of these entities and therefore beneficially owns such shares. Each of the Summit Funds, Mr. Chung, Mr. Black and Dr. Frances disclaim beneficial ownership of the shares, except, in each case, to the extent of such person's or entity's pecuniary interest therein.

Shares held of record by the Eric Shuey Gift Trust. The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of Securities Exchange Act of 1934 or for any other purpose.

The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of the Exchange Act of 1934 (the "Exchange Act") or for any other purpose.

The price reported is a weighted average price. These shares were sold in multiple transactions ranging from $8.40 to $8.89 inclusive. The Reporting Person undertakes to provide to the Company, any security holder of the Company or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of the Exchange Act or for any other purpose.

The price reported is a weighted average price. These shares were sold in multiple transactions ranging from $8.40 to $8.89 inclusive. The Reporting Person undertakes to provide to the Company, any security holder of the Company or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of the Exchange Act of 1934 (the "Exchange Act") or for any other purpose.

The price reported is a weighted average price. These shares were sold in multiple transactions ranging from $7.00 to $7.095 inclusive. The Reporting Person undertakes to provide to the Company, any security holder of the Company or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of the Exchange Act or for any other purpose.

The price reported is a weighted average price. These shares were sold in multiple transactions ranging from $7.00 to $7.095 inclusive. The Reporting Person undertakes to provide to the Company, any security holder of the Company or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of the Exchange Act of 1934 (the "Exchange Act") or for any other purpose.

The price reported is a weighted average price. These shares were sold in multiple transactions ranging from $7.00 to $7.005 inclusive. The Reporting Person undertakes to provide to the Company, any security holder of the Company or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of the Exchange Act or for any other purpose.

The price reported is a weighted average price. These shares were sold in multiple transactions ranging from $7.00 to $7.005 inclusive. The Reporting Person undertakes to provide to the Company, any security holder of the Company or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of the Exchange Act of 1934 (the "Exchange Act") or for any other purpose.

The price reported is a weighted average price. These shares were sold in multiple transactions ranging from $7.00 to $7.02 inclusive. The Reporting Person undertakes to provide to the Company, any security holder of the Company or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of the Exchange Act or for any other purpose.

The price reported is a weighted average price. These shares were sold in multiple transactions ranging from $7.00 to $7.02 inclusive. The Reporting Person undertakes to provide to the Company, any security holder of the Company or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these securities on this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities for purposes of Section 16 of the Exchange Act of 1934 (the "Exchange Act") or for any other purpose.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of restricted stock units ("RSUs") that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested RSUs and do not constitute any open-market sale.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of restricted stock units ("RSUs") that vested on March 24, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested RSUs and do not constitute any open-market sale.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of restricted stock units ("RSUs") that vested on March 17, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested RSUs and do not constitute any open-market sale.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of PSUs that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested PSUs and do not constitute any open-market sale.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of PSUs that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested PSUs and do not constitute any open-market sale.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of PSUs that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested PSUs and do not constitute any open-market sale.

Represents PSUs previously granted to the Reporting Person on February 27, 2025, which vested on March 9, 2026.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of restricted stock units ("RSUs") that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested RSUs and do not constitute any open-market sale.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of PSUs that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested PSUs and do not constitute any open-market sale.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of restricted stock units ("RSUs") that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested RSUs and do not constitute any open-market sale.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of PSUs that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested PSUs and do not constitute any open-market sale.

Represents performance-based restricted stock units ("PSUs") previously granted to the Reporting Person on March 6, 2025, which vested on March 9, 2026.

Represents performance-based restricted stock units ("PSUs") previously granted to the Reporting Person on March 6, 2025, which vested on March 9, 2026.

Represents performance-based restricted stock units ("PSUs") previously granted to the Reporting Person on March 6, 2025, which vested on March 9, 2026.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of PSUs that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested PSUs and do not constitute any open-market sale.

Represents performance-based restricted stock units ("PSUs") previously granted to the Reporting Person on June 11, 2025, which vested on March 9, 2026.

Represents PSUs previously granted to the Reporting Person on March 24, 2025, which vested on March 9, 2026.

Represents performance-based restricted stock units ("PSUs") previously granted to the Reporting Person on March 6, 2025, which vested on March 9, 2026.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of PSUs that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested PSUs and do not constitute any open-market sale.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of restricted stock units ("RSUs") that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested RSUs and do not constitute any open-market sale.

Represents performance-based restricted stock units ("PSUs") previously granted to the Reporting Person on March 6, 2025, which vested on March 9, 2026.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of restricted stock units ("RSUs") that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested RSUs and do not constitute any open-market sale.

Represents PSUs previously granted to the Reporting Person on February 27, 2025, which vested on March 9, 2026.

Represents the number of shares withheld by the Issuer to satisfy tax withholding obligations in connection with the net settlement of PSUs that vested on March 9, 2026. The shares withheld represent a reduction of shares issued to the Reporting Person upon settlement of vested PSUs and do not constitute any open-market sale.