BlackRock Portfolio Management LLC discloses 4.1% REGENXBIO (RGNX) stake

Rhea-AI Filing Summary

REGENXBIO Inc. received an updated ownership report from BlackRock Portfolio Management LLC, which filed Amendment No. 1 to its Schedule 13G. BlackRock reports beneficial ownership of 2,085,619 shares of REGENXBIO common stock, representing 4.1% of the outstanding shares as of the stated event date. BlackRock has sole voting power over 1,818,311 shares and sole dispositive power over the full 2,085,619 shares, with no shared voting or dispositive power.

The filing explains that these holdings reflect securities beneficially owned, or deemed to be beneficially owned, by certain business units of BlackRock, Inc. and its affiliates. Various underlying clients have the right to receive dividends or sale proceeds, but no single client holds more than five percent of REGENXBIO’s outstanding common stock. BlackRock certifies that the securities were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control of REGENXBIO.

AI-generated analysis. How Rhea-AI works. Not financial advice.

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Accepted by SEC EDGAR 01/21/2026 - 12:26 PM Learn about SEC filing dates

FAQ

How many REGENXBIO (RGNX) shares does BlackRock Portfolio Management LLC report owning?

BlackRock Portfolio Management LLC reports beneficial ownership of 2,085,619 shares of REGENXBIO Inc. common stock, according to the Schedule 13G/A filing.

What percentage of REGENXBIO (RGNX) does BlackRock Portfolio Management LLC hold?

The filing states that BlackRock Portfolio Management LLC beneficially owns 4.1% of the outstanding REGENXBIO Inc. common stock.

Does BlackRock have voting and dispositive power over its REGENXBIO (RGNX) shares?

Yes. BlackRock Portfolio Management LLC has sole voting power over 1,818,311 shares and sole dispositive power over 2,085,619 shares, with no shared voting or dispositive power reported.

Is BlackRock’s REGENXBIO (RGNX) stake intended to influence control of the company?

The certification states the securities were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing the control of REGENXBIO Inc..

Who ultimately benefits from the REGENXBIO (RGNX) shares held by BlackRock Portfolio Management LLC?

The filing notes that various persons have the right to receive dividends or sale proceeds from the REGENXBIO common stock, and that no one person’s interest exceeds five percent of the total outstanding common shares.

What type of filer is BlackRock Portfolio Management LLC in this REGENXBIO (RGNX) Schedule 13G/A?

BlackRock Portfolio Management LLC is classified as "HC" (holding company or control person) in the Schedule 13G/A.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 1)

REGENXBIO INC

(Name of Issuer)

Common Stock

(Title of Class of Securities)

75901B107

(CUSIP Number)

12/31/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. 75901B107

1

Names of Reporting Persons

BlackRock Portfolio Management LLC

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 1,818,311.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 2,085,619.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

2,085,619.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

4.1 %

12

Type of Reporting Person (See Instructions)

HC

SCHEDULE 13G

Item 1.
(a)	Name of issuer: REGENXBIO INC
(b)	Address of issuer's principal executive offices: 9804 MEDICAL CENTER DRIVE ROCKVILLE MD 20850
Item 2.
(a)	Name of person filing: BlackRock Portfolio Management LLC In accordance with SEC Release No. 34-39538 (January 12, 1998), this Schedule 13G reflects the securities beneficially owned, or deemed to be beneficially owned, by certain business units (collectively, the "Reporting Business Units") of BlackRock, Inc. and its subsidiaries and affiliates. It does not include securities, if any, beneficially owned by other business units whose beneficial ownership of securities are disaggregated from that of the Reporting Business Units in accordance with such release.
(b)	Address or principal business office or, if none, residence: BlackRock Portfolio Management LLC, 50 Hudson Yards New York, NY 10001
(c)	Citizenship: See Item 4 of Cover Page
(d)	Title of class of securities: Common Stock
(e)	CUSIP No.: 75901B107
Item 4.	Ownership
(a)	Amount beneficially owned: 2085619
(b)	Percent of class: 4.1 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 1818311
	(ii) Shared power to vote or to direct the vote: 0
	(iii) Sole power to dispose or to direct the disposition of: 2085619
	(iv) Shared power to dispose or to direct the disposition of: 0
Item 5.	Ownership of 5 Percent or Less of a Class.
	Ownership of 5 percent or less of a class
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required. Various persons have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of the common stock of REGENXBIO INC. No one person's interest in the common stock of REGENXBIO INC is more than five percent of the total outstanding common shares.
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	If a parent holding company has filed this schedule, pursuant to Rule 13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary. See Exhibit 99
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

BlackRock Portfolio Management LLC

Signature:	Spencer Fleming
Name/Title:	Managing Director
Date:	01/21/2026

Exhibit Information

Exhibit 24: Power of Attorney Exhibit 99: Item 7