RNAC · Cartesian Therapeutics, Inc.

On April 2, 2026, a trust (the "Trust") for the benefit of the reporting person's spouse and children elected to convert a portion of its shares of the issuer's Series A Non-Voting Convertible Preferred Stock into shares of the issuer's common stock. The remaining shares of the issuer's Series A Non-Voting Convertible Preferred Stock held by the Trust are subject to a beneficial ownership limitation.

On November 13, 2023, the issuer acquired the private Delaware corporation which was then known as Cartesian Therapeutics, Inc. in accordance with the terms of an Agreement and Plan of Merger, dated November 13, 2023 (the "Merger"). These securities represent merger consideration payable as a result of the closing of the Merger and securities purchased in a private placement in November 2023.

Shares are held by the Trust for the benefit of the reporting person's spouse and children. The reporting person's spouse is a trustee of the Trust.

On April 2, 2026, Seven One Eight Three Four Irrevocable Trust (the "Trust") elected to convert a portion of its shares of the issuer's Series A Non-Voting Convertible Preferred Stock into shares of the issuer's common stock. The remaining shares of the issuer's Series A Non-Voting Convertible Preferred Stock held by the Trust are subject to a beneficial ownership limitation.

Shares are held by the Trust. The reporting person is a trustee of the Trust.

On April 2, 2026, Seven One Eight Three Four Irrevocable Trust (the "Trust") elected to convert a portion of its shares of the issuer's Series A Non-Voting Convertible Preferred Stock into shares of the issuer's common stock. The remaining shares of the issuer's Series A Non-Voting Convertible Preferred Stock held by the Trust are subject to a beneficial ownership limitation.

On November 13, 2023, the issuer acquired the private Delaware corporation which was then known as Cartesian Therapeutics, Inc. in accordance with the terms of an Agreement and Plan of Merger, dated November 13, 2023 (the "Merger"). These securities represent merger consideration payable as a result of the closing of the Merger and securities purchased in a private placement in November 2023.

Shares are held by the Trust. The reporting person is a trustee of the Trust.

On April 2, 2026, a trust (the "Trust") for the benefit of the reporting person's spouse and children elected to convert a portion of its shares of the issuer's Series A Non-Voting Convertible Preferred Stock into shares of the issuer's common stock. The remaining shares of the issuer's Series A Non-Voting Convertible Preferred Stock held by the Trust are subject to a beneficial ownership limitation.

Shares are held by the Trust for the benefit of the reporting person's spouse and children. The reporting person's spouse is a trustee of the Trust.

Shares sold to satisfy withholding tax obligations upon the vesting of restricted stock units and to cover related broker fees.

Shares sold to satisfy withholding tax obligations upon the vesting of restricted stock units and to cover related broker fees.

Shares sold to satisfy withholding tax obligations upon the vesting of restricted stock units and to cover related broker fees.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest as to 25% on January 2, 2027. The remainder of the underlying shares will vest in three equal annual installments thereafter so that the underlying shares will be fully vested on January 2, 2030.

This option vests as to 25% on January 2, 2027. The remainder of the underlying shares will vest in 36 equal monthly installments thereafter.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest in full on January 2, 2027.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest in full on January 2, 2027.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest in full on January 2, 2027.

This option vests as to 25% on January 2, 2027. The remainder of the underlying shares will vest in 36 equal monthly installments thereafter.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest as to 25% on January 2, 2027. The remainder of the underlying shares will vest in three equal annual installments thereafter so that the underlying shares will be fully vested on January 2, 2030.

This option vests as to 25% on January 2, 2027. The remainder of the underlying shares will vest in 36 equal monthly installments thereafter.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest in full on January 2, 2027.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest in full on January 2, 2027.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest as to 25% on January 2, 2027. The remainder of the underlying shares will vest in three equal annual installments thereafter so that the underlying shares will be fully vested on January 2, 2030.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest in full on January 2, 2027.

This option vests as to 25% on January 2, 2027. The remainder of the underlying shares will vest in 36 equal monthly installments thereafter.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest as to 25% on January 2, 2027. The remainder of the underlying shares will vest in three equal annual installments thereafter so that the underlying shares will be fully vested on January 2, 2030.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest as to 25% on January 2, 2027. The remainder of the underlying shares will vest in three equal annual installments thereafter so that the underlying shares will be fully vested on January 2, 2030.

This option vests as to 25% on January 2, 2027. The remainder of the underlying shares will vest in 36 equal monthly installments thereafter.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest in full on January 2, 2027.

On November 13, 2023, the issuer acquired the Delaware corporation which was then-known as Cartesian Therapeutics, Inc. ("Old Cartesian") in accordance with the terms of an Agreement and Plan of Merger, dated November 13, 2023. Options to purchase Old Cartesian common stock held by the reporting person were converted into options to purchase shares of the issuer's common stock in connection with the merger.

These options are currently fully vested and exercisable.

Each Restricted Stock Unit represents a contingent right to receive one share of common stock, which will vest in three equal annual installments following the date of grant so that the underlying shares will be fully vested on December 16, 2028.

This award will vest in 36 equal monthly installments, so that it shall be fully vested on December 16, 2028.

The price reported is a weighted average price. The shares were purchased in multiple transactions at per share prices ranging from $6.80 to $6.90. The Reporting Person undertakes to provide upon request to the SEC staff, the Issuer, or any stockholder of the Issuer, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote.

On November 13, 2023, the issuer acquired the Delaware corporation which was then-known as Cartesian Therapeutics, Inc. ("Old Cartesian") in accordance with the terms of an Agreement and Plan of Merger, dated November 13, 2023. Options to purchase Old Cartesian common stock held by the reporting person were converted into options to purchase shares of the issuer's common stock in connection with the merger.

These options are currently fully vested and exercisable.

This option vests as to 25% on October 27, 2026. The remainder of the underlying shares will vest in three equal annual installments thereafter so that the underlying shares will be fully vested on October 27, 2029.

On November 13, 2023, the issuer acquired the Delaware corporation which was then-known as Cartesian Therapeutics, Inc. ("Old Cartesian") in accordance with the terms of an Agreement and Plan of Merger, dated November 13, 2023. Options to purchase Old Cartesian common stock held by the reporting person were converted into options to purchase shares of the issuer's common stock in connection with the merger.

These options are currently fully vested and exercisable.

On November 13, 2023, the issuer acquired the Delaware corporation which was then-known as Cartesian Therapeutics, Inc. ("Old Cartesian") in accordance with the terms of an Agreement and Plan of Merger, dated November 13, 2023. Options to purchase Old Cartesian common stock held by the reporting person were converted into options to purchase shares of the issuer's common stock in connection with the merger.

These options are currently fully vested and exercisable.

The price reported is a weighted average price. The shares were purchased in multiple transactions at per share prices ranging from $10.395 to $11.00. The Reporting Person undertakes to provide upon request to the SEC staff, the Issuer, or any stockholder of the Issuer, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote.

Held by TAS Partners LLC. The reporting person is the managing member of TAS Partners LLC. The reporting person disclaims beneficial ownership of the securities held by TAS Partners LLC except to the extent of his pecuniary interest therein, if any.

The price reported is a weighted average price. The shares were purchased in multiple transactions at per share prices ranging from $10.395 to $11.00. The Reporting Person undertakes to provide upon request to the SEC staff, the Issuer, or any stockholder of the Issuer, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote.

Held by TAS Partners LLC. The reporting person is the managing member of TAS Partners LLC. The reporting person disclaims beneficial ownership of the securities held by TAS Partners LLC except to the extent of his pecuniary interest therein, if any.

The price reported is a weighted average price. The shares were purchased in multiple transactions at per share prices ranging from $9.918 to $10.7461. The Reporting Person undertakes to provide upon request to the SEC staff, the Issuer, or any stockholder of the Issuer, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote.

Held by TAS Partners LLC. The reporting person is the managing member of TAS Partners LLC. The reporting person disclaims beneficial ownership of the securities held by TAS Partners LLC except to the extent of his pecuniary interest therein, if any.