REGENXBIO Form 144: planned sale of 20,811 shares for $254,310

Rhea-AI Filing Summary

REGENXBIO, Inc. (RGNX) filed a Form 144 notifying the proposed sale of 20,811 common shares with an aggregate market value of $254,310.42, scheduled for 10/09/2025 and to be executed on the NASDAQ. The shares were acquired as Restricted Stock Units on 01/01/2025, and the filer indicates the securities were granted by the issuer.

The filing discloses recent Rule 10b5-1 sales by the same person: 7,624 shares sold on 09/29/2025 for $76,434.41 and 7,734 shares sold on 09/10/2025 for $77,530.26. Outstanding shares are listed as 50,514,216, making the proposed sale a small fraction of total outstanding equity.

Positive

• Restricted Stock Units were acquired on 01/01/2025, indicating compensation alignment with the issuer
• Planned sale is executed through a broker (Morgan Stanley Smith Barney LLC), suggesting orderly disposition
• Prior 10b5-1 sales on 09/10/2025 and 09/29/2025 show use of pre‑arranged trading procedures

Negative

• The filer proposes to sell 20,811 shares on 10/09/2025, which reduces the insider's stake in the issuer

Form 144 Filer Information	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 144 NOTICE OF PROPOSED SALE OF SECURITIES PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF 1933
FORM 144

144: Filer Information

Filer CIK
Filer CCC
Is this a LIVE or TEST Filing?	LIVE TEST
Submission Contact Information
Name
Phone
E-Mail Address

144: Issuer Information

Name of Issuer

SEC File Number

Address of Issuer

Phone

Name of Person for Whose Account the Securities are To Be Sold

See the definition of "person" in paragraph (a) of Rule 144. Information is to be given not only as to the person for whose account the securities are to be sold but also as to all other persons included in that definition. In addition, information shall be given as to sales by all persons whose sales are required by paragraph (e) of Rule 144 to be aggregated with sales for the account of the person filing this notice.

Relationship to Issuer

Relationship to Issuer

144: Securities Information

Title of the Class of Securities To Be Sold	Name and Address of the Broker	Number of Shares or Other Units To Be Sold	Aggregate Market Value	Number of Shares or Other Units Outstanding	Approximate Date of Sale	Name the Securities Exchange
Common	Morgan Stanley Smith Barney LLC Executive Financial Services 1 New York Plaza 8th Floor New York NY 10004	20811	254310.42	50514216	10/09/2025	NASDAQ

Furnish the following information with respect to the acquisition of the securities to be sold and with respect to the payment of all or any part of the purchase price or other consideration therefor:

144: Securities To Be Sold

Title of the Class	Date you Acquired	Nature of Acquisition Transaction	Name of Person from Whom Acquired	Is this a Gift?	Date Donor Acquired	Amount of Securities Acquired	Date of Payment	Nature of Payment *
Common	01/01/2025	Restricted Stock Units	Issuer			20811	01/01/2025	N/A

* If the securities were purchased and full payment therefor was not made in cash at the time of purchase, explain in the table or in a note thereto the nature of the consideration given. If the consideration consisted of any note or other obligation, or if payment was made in installments describe the arrangement and state when the note or other obligation was discharged in full or the last installment paid.

Furnish the following information as to all securities of the issuer sold during the past 3 months by the person for whose account the securities are to be sold.

144: Securities Sold During The Past 3 Months

Name and Address of Seller	Title of Securities Sold	Date of Sale	Amount of Securities Sold	Gross Proceeds
10b5-1 Sales for CURRAN M SIMPSON 9804 Medical Center Drive Rockville MD 20850	Common	09/29/2025	7624	76434.41
10b5-1 Sales for CURRAN M SIMPSON 9804 Medical Center Drive Rockville MD 20850	Common	09/10/2025	7734	77530.26

144: Remarks and Signature

Remarks

Date of Notice

Date of Plan Adoption or Giving of Instruction, If Relying on Rule 10b5-1

ATTENTION:

The person for whose account the securities to which this notice relates are to be sold hereby represents by signing this notice that he does not know any material adverse information in regard to the current and prospective operations of the Issuer of the securities to be sold which has not been publicly disclosed. If such person has adopted a written trading plan or given trading instructions to satisfy Rule 10b5-1 under the Exchange Act, by signing the form and indicating the date that the plan was adopted or the instruction given, that person makes such representation as of the plan adoption or instruction date.

Signature

ATTENTION: Intentional misstatements or omission of facts constitute Federal Criminal Violations (See 18 U.S.C. 1001)

FAQ

What does the Form 144 for RGNX announce?

It notifies a proposed sale of 20,811 common shares with an aggregate market value of $254,310.42, scheduled for 10/09/2025.

How were the shares to be sold acquired?

The 20,811 shares were acquired as Restricted Stock Units on 01/01/2025 and were issued by the company.

Who is handling the sale of RGNX shares?

The broker listed is Morgan Stanley Smith Barney LLC, located at 1 New York Plaza, New York, NY, and the sale is to occur on the NASDAQ.

Has the filer sold RGNX shares recently?

Yes. The filing shows Rule 10b5-1 sales of 7,734 shares on 09/10/2025 for $77,530.26 and 7,624 shares on 09/29/2025 for $76,434.41.

How large is the proposed sale relative to shares outstanding?

Outstanding shares are listed as 50,514,216, so the proposed 20,811 share sale represents a small percentage of total equity.