Explanatory Note
This Amendment No. 1 (the Amendment No. 1) amends the Schedule 13D filed with the SEC on
September 16, 2015 (the Schedule 13D) with respect to the common stock, par value $0.0001 per share (the common stock), of REGENXBIO Inc., a Delaware corporation (the Company). This amendment reflects certain
estate planning transactions that were completed on September 16, 2020. As a result of these transactions and the prior distribution of the Companys shares held by FOXKISER Holdings, LLC (FoxKiser Holdings), Allan M. Fox has
been added as a reporting person and The Allan M. Fox Trust (U/A/D April 21, 2015) (the Fox Trust), The Allan M. Fox Revocable Trust (the Fox Revocable Trust) and FoxKiser Holdings ceased to be reporting persons with
respect to the Companys securities.
Item 1. Security and Issuer.
This Amendment No. 1 relates to the common stock of REGENXBIO Inc., which maintains its principal executive office at 9600
Blackwell Road, Suite 210, Rockville, Maryland 20850.
Item 2. Identity and Background.
(a) This Amendment No. 1 is being filed by Allan M. Fox (the Reporting Person).
(b) The business address of the Reporting Person is 1701 Pennsylvania Avenue, NW, Suite 900, Washington, DC 20006
(c) The Reporting Person is the founding partner of FOXKISER LLP, which has its business address at 1701 Pennsylvania Ave., NW, Suite 900,
Washington, DC 20006.
(d) (e) During the past five years, the Reporting Person has not been (i) convicted in a criminal
proceeding (excluding traffic violations or similar misdemeanors) or (ii) a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of which the Reporting Person was or is subject to a
judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, United States federal or state securities laws or a finding of any violation with respect to such laws.
(f) The Reporting Person is a citizen of the United States of America.
Item 3. Source and Amount of Funds or Other Consideration.
Following the completion of the Companys initial public offering of common stock on September 22, 2015, the Fox
Trust held 722,485 shares of the Companys common stock, the Fox Revocable Trust held 2,054,863 shares of the Companys common stock and FoxKiser Holdings held 443,700 shares of the Companys common stock. The shares held by FoxKiser
Holdings were distributed to its investors on a pro rata basis in July 2018, which resulted in the distribution of 266,220 shares of the Companys common stock to the Fox Revocable Trust. In addition to these holdings, the Reporting Person
receives equity compensation in connection with his service on the Companys board of directors.
In the series of
estate planning transactions consummated on July 27, 2020 and completed on September 16, 2020 as described in Item 5 below, shares controlled by the Reporting Person, the Fox Trust and the Fox Revocable Trust were transferred to limited
liability companies for which the Reporting Person serves as manager. The membership interests of such limited liability companies are owned by trusts established by the Reporting Person and his spouse. There was no consideration paid for the
transfers of shares of the Companys common stock or for the membership interests of the limited liability companies that hold such shares. In addition to these holdings, the Reporting Person holds shares of the Companys common stock
through a grantor retained annuity trust and shares issuable upon the exercise of stock options that were granted in connection with his service on the Companys board of directors.
Item 4. Purpose of Transaction.
As stated above, the share transfers to the entities referenced herein were made for estate planning purposes. The Reporting
Person holds the shares of the Company discussed herein for investment. The Reporting Person may, from time to time, depending on market conditions and other factors deemed relevant by the Reporting Person, acquire shares of common stock or other
capital stock of the Company and/or dispose of shares. Any actions the Reporting Person might undertake will be dependent upon the Reporting Persons review of numerous factors, including, among other things, the price levels of the common
stock, general market and economic conditions, ongoing evaluation of the Companys business, financial condition, operations and prospects, the relative attractiveness of alternative business and investment opportunities, and other future
developments.
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