Emily English - 30 Dec 2025 Form 4 Insider Report for Cartesian Therapeutics, Inc. (RNAC)

Reporting relationship: Chief Operations Officer
Issuer ticker: RNAC
Reported as of: 30 Dec 2025
Net transaction value: +$24,750
SEC form: 4
Accepted by SEC: 02 Jan 2026, 16:03:30 UTC
Prior SEC filing: 02 Dec 2025
Next SEC filing: 06 Jan 2026
Source filing: View source filing
Reporting owner signature: /s/ Matthew Bartholomae, Attorney-in-Fact for Emily English

Key filing fact

Emily English filed Form 4 for Cartesian Therapeutics, Inc. (RNAC) on 02 Jan 2026.

Key facts

This page summarizes Emily English's Form 4 filing for Cartesian Therapeutics, Inc. (RNAC).
2 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 02 Jan 2026, 16:03.

Change

Previous filing in this sequence was filed on 02 Dec 2025.
Current net transaction value: +$24,750.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0002019791 Primary reporting owner

English Emily

Relationship: Chief Operations Officer
Address: C/O CARTESIAN THERAPEUTICS, INC., 7495 NEW HORIZON WAY, FREDERICK
Signature: /s/ Matthew Bartholomae, Attorney-in-Fact for Emily English
Signature date: 02 Jan 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

RNAC transaction

Common Stock

Options Exercise

Transaction value: $24,750
Shares: +7,500
Change %: +12%
Price: $3.30
Shares after: 70,226
Date: 30 Dec 2025
Ownership: Direct

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

RNAC transaction Derivative

Stock Option (Right to Buy)

Options Exercise

Transaction value
Shares: -7,500
Change %: -28%
Price
Shares after: 19,369
Date: 30 Dec 2025
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 7,500
Exercise price: $3.30
Footnotes: F1, F2

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 2 footnotes

Footnote F1

These options are currently fully vested and exercisable.

Footnote F2

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.