Explanatory Note
This Amendment No. 2 (“Amendment No. 2”) to Schedule 13D relates to the Ordinary Shares, nominal value $0.000042 per
share (the “Ordinary Shares”) represented by American Depositary Shares (the “ADSs”), each of which represents one Ordinary Share of Autolus Therapeutics plc, a public limited company organized under the laws of
England and Wales (the “Issuer”), and amends and supplements the initial statement on Schedule 13D filed on November 16, 2021, as amended by Amendment No. 1 filed on December 13, 2022, (as amended, the
“Schedule 13D”). The address of the principal executive office of the Issuer is The MediaWorks, 191 Wood Lane, London W12 7FP, United Kingdom. Except as specifically provided herein, this Amendment No. 2 does not modify any of
the information previously reported in the Schedule 13D. Capitalized terms used but not defined in this Amendment No. 2 shall have the same meanings ascribed to them in the Schedule 13D.
This Amendment No. 2 is being filed to update the aggregate percentage of the Issuer’s Ordinary Shares (including in the form of ADSs) beneficially
owned by the Reporting Persons due to dilution caused by the Issuer’s issuance of additional Ordinary Shares (including in the form of ADSs) from time to time since the date of the filing of Amendment No. 1 to Schedule 13D and not in
connection with a purchase or disposition of any Ordinary Shares or ADSs by the Reporting Person.
Item 2. Identity and Background
Item 2 of the Schedule 13D is hereby amended by incorporating herein by reference the information set forth on the updated Schedule I attached hereto.
Item 5. Interest in Securities of the Issuer
Items
5(a) and (b) of the Schedule 13D are each hereby amended and restated in their entirety as follows:
(a) and (b) Calculations of the percentage
of the ADSs representing Ordinary Shares beneficially owned are based on 266,036,128 Ordinary Shares outstanding as of May 13, 2024 as reported by the Issuer in the Quarterly Report on Form 10-Q filed
with the Securities and Exchange Commission on May 17, 2024 and takes into account the 3,265,306 Ordinary Shares underlying the warrants beneficially owned by the Reporting Persons that are exercisable within 60 days.
The aggregate number and percentage of the ADSs representing Ordinary Shares beneficially owned by each Reporting Person and, for each Reporting Person, the
number of shares as to which there is sole power to vote or to direct the vote, shared power to vote or to direct the vote, sole power to dispose or to direct the disposition, or shared power to dispose or to direct the disposition are set forth on
rows 7 through 11 and row 13 of the cover pages of this Schedule 13D and are incorporated herein by reference.
As of the date hereof, BXLS V directly
beneficially owns 23,750,917 ADSs representing the same number of Ordinary Shares, which includes 3,265,306 shares underlying warrants to purchase ADSs that are exercisable within 60 days.
Autobahn GP is the general partner of BXLS V. Blackstone Clarus GP L.L.C. is the general partner of Autobahn GP. The sole member of Blackstone Clarus GP
L.L.C. is Blackstone Holdings I L.P. The general partner of Blackstone Holdings I L.P. is Blackstone Holdings I/II GP L.L.C. The sole member of Blackstone Holdings I/II GP L.L.C. is Blackstone Inc. The sole holder of the Series II preferred stock of
Blackstone Inc. is Blackstone Group Management L.L.C. Blackstone Group Management L.L.C. is wholly-owned by Blackstone’s senior managing directors and controlled by its founder, Stephen A. Schwarzman.
Neither the filing of this Schedule 13D nor any of its contents shall be deemed to constitute an admission that any Reporting Person is the beneficial owner
of the ADSs representing Ordinary Shares referred to herein for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, or for any other purpose and such beneficial ownership is expressly disclaimed (other than by the
Reporting Persons, to the extent they directly hold ADSs). The filing of this statement should not be construed to be an admission that any member of the Reporting Persons are members of a “group” for the purposes of Sections 13(d) and
13(g) of the Exchange Act.
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