STOCK TITAN

Trust linked to RNAC holder Kalayoglu converts preferred into 758,001 common shares

Filing Impact
(Neutral)
Filing Sentiment
(Neutral)
Form Type
4

Rhea-AI Filing Summary

Cartesian Therapeutics, Inc. insider filing shows a trust converting preferred stock into common shares. On April 2, 2026, a trust for the benefit of Murat Kalayoglu’s spouse and children exercised 22,740.03 shares of Series A Non-Voting Convertible Preferred Stock to acquire 758,001 shares of common stock at a conversion price of $0.00 per share.

After the transaction, the trust held 33,662.224 shares of the preferred stock and 5,313,261 shares of common stock indirectly. Murat Kalayoglu also held 506,999 shares of common stock directly. The filing reflects a derivative exercise and conversion, not an open-market purchase or sale.

Positive

  • None.

Negative

  • None.
Insider Kalayoglu Murat
Role 10% Owner
Type Security Shares Price Value
Exercise Series A Non-Voting Convertible Preferred Stock 22,740.03 $0.00 --
Exercise Common Stock 758,001 $0.00 --
holding Common Stock -- -- --
Holdings After Transaction: Series A Non-Voting Convertible Preferred Stock — 33,662.224 shares (Indirect, by trust); Common Stock — 5,313,261 shares (Indirect, by trust); Common Stock — 506,999 shares (Direct)
Footnotes (1)
  1. 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. 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.
Preferred shares exercised 22,740.03 shares Series A Non-Voting Convertible Preferred Stock exercised on April 2, 2026
Common shares acquired 758,001 shares Common stock received upon preferred conversion on April 2, 2026
Conversion price $0.00 per share Stated conversion price for preferred into common stock
Preferred shares remaining 33,662.224 shares Series A Non-Voting Convertible Preferred Stock held by trust after conversion
Indirect common holdings 5,313,261 shares Common stock held indirectly by trust following transactions
Direct common holdings 506,999 shares Common stock held directly by Murat Kalayoglu after reported transactions
Series A Non-Voting Convertible Preferred Stock financial
"a 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"
Series A non-voting convertible preferred stock is an early-round ownership share that gives holders priority over common shareholders for payouts and protections, but does not grant voting control. It can be exchanged later for common shares—like a coupon that can be turned into regular stock—allowing investors to share in upside while limiting immediate influence on company decisions; this affects potential returns, dilution for other shareholders, and the balance of control in future financing or sale events.
beneficial ownership limitation financial
"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"
A beneficial ownership limitation is a rule that caps the percentage of a company’s shares an investor can be treated as owning or controlling for voting, regulatory or tax purposes. It matters to investors because it can restrict how many shares a person or group can buy or vote, affect takeover chances, and influence share liquidity and value — like a speed limit that prevents any single driver from taking over the whole road.
merger consideration financial
"These securities represent merger consideration payable as a result of the closing of the Merger"
Merger consideration is the total payment a company or buyer offers to shareholders of a target company in exchange for combining the two businesses, and can include cash, shares in the surviving company, debt assumption, or a mix of these. Investors care because the form and amount affect the deal’s value, tax consequences, immediate cash received versus future ownership, and the risk and upside of holding new shares — similar to choosing between cash now or stock that could grow later.
private placement financial
"and securities purchased in a private placement in November 2023"
A private placement is a way for companies to raise money by selling securities directly to a small group of investors instead of through a public offering. This process is often quicker and less regulated, making it similar to offering a special, exclusive investment opportunity to select individuals or institutions. For investors, it can provide access to unique investment options that are not available on public markets.
derivative security financial
"transaction code description: Exercise or conversion of derivative security"
A derivative security is a financial contract whose value comes from the price or performance of something else, such as a stock, bond, commodity, or market index. For investors it acts like an insurance policy or a wager: it can be used to protect against losses, lock in prices, or amplify gains and losses, so it can change a portfolio’s risk and potential return without owning the underlying asset directly.
SEC Form 4
FORM 4UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number:3235-0287
Estimated average burden
hours per response:0.5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.
1. Name and Address of Reporting Person*
Kalayoglu Murat

(Last)(First)(Middle)
C/O SOAR BIO, LLC
7144 13TH PL NW

(Street)
WASHINGTON DISTRICT OF COLUMBIA 20012

(City)(State)(Zip)

UNITED STATES

(Country)
2. Issuer Name and Ticker or Trading Symbol
Cartesian Therapeutics, Inc. [ RNAC ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
DirectorX10% Owner
Officer (give title below)Other (specify below)
2a. Foreign Trading Symbol
3. Date of Earliest Transaction (Month/Day/Year)
04/02/2026
6. Individual or Joint/Group Filing (Check Applicable Line)
XForm filed by One Reporting Person
Form filed by More than One Reporting Person
4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year)2A. Deemed Execution Date, if any (Month/Day/Year)3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeVAmount(A) or (D)Price
Common Stock04/02/2026M758,001A(1)5,313,261Iby trust(2)
Common Stock506,999D
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year)3A. Deemed Execution Date, if any (Month/Day/Year)4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 6. Date Exercisable and Expiration Date (Month/Day/Year)7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares
Series A Non-Voting Convertible Preferred Stock(1)04/02/2026M22,740.03 (1) (1)Common Stock758,001(3)33,662.224Iby trust(2)
Explanation of Responses:
1. 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.
2. 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.
3. 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.
/s/ Murat Kalayoglu04/06/2026
** Signature of Reporting PersonDate
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What insider activity did RNAC report for Murat Kalayoglu?

The filing shows a trust associated with Murat Kalayoglu converted Series A Non-Voting Convertible Preferred Stock into 758,001 shares of common stock. This was a derivative exercise at a $0.00 per share conversion price, not an open-market buy or sell transaction.

Who actually holds the RNAC shares involved in this Form 4?

The shares are held by a trust for the benefit of Murat Kalayoglu’s spouse and children. The trust, not Kalayoglu personally, holds the indirectly owned preferred and common shares, with his spouse serving as a trustee of the trust structure.

How many RNAC common shares were acquired in this conversion?

The trust exercised 22,740.03 shares of Series A Non-Voting Convertible Preferred Stock into 758,001 shares of Cartesian Therapeutics common stock. This reflects a derivative conversion event at a stated conversion price of $0.00 per share, rather than a cash purchase.

What are Murat Kalayoglu’s reported RNAC holdings after the transactions?

Following the conversion, the trust held 5,313,261 shares of Cartesian Therapeutics common stock indirectly, plus 33,662.224 remaining preferred shares. Separately, Murat Kalayoglu held 506,999 common shares directly, giving him both indirect and direct ownership interests reported in the filing.

Did the RNAC Form 4 include any insider sales or gifts?

The Form 4 data show derivative exercises and updated holdings, but no reported open-market sales, gifts, or tax-withholding dispositions. Transactions were coded as derivative exercises or conversions, with one additional line item reflecting updated direct common stock holdings only.