UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 2)*

Mandiant, Inc.

(Name of Issuer)

Common Stock, par value $0.0001 per share

(Title of Class of Securities)

562662106

(CUSIP Number)

John G. Finley

Blackstone Inc.

345 Park Avenue

New York, New York 10154

Tel: (212) 583-5000

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

September 12, 2022

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. ☐

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 for other parties to whom copies are to be sent.

*	The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Delta Lower Holdings DE L.P.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS BTO FD Delta Holdings DE L.P.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Delta Lower Holdings Manager L.L.C.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Delta Holdings DE L.P.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS BTO Holdings Manager L.L.C.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Tactical Opportunities Associates L.L.C.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS BTOA L.L.C.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Holdings III L.P.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Quebec, Canada

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Holdings III GP L.P.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Holdings III GP Management L.L.C.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS BTO FD Delta Holdings Manager L.L.C.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Tactical Opportunities Fund – FD L.P.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Tactical Opportunities Associates III – NQ L.P.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS BTO DE GP – NQ L.L.C.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Holdings II L.P.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Holdings I/II GP L.L.C.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Inc.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Blackstone Group Management L.L.C.
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

CUSIP No. 562662106


1		NAMES OF REPORTING PERSONS Stephen A. Schwarzman
2		CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ☐ (b) ☒
3		SEC USE ONLY
4		SOURCE OF FUNDS (SEE INSTRUCTIONS) OO
5		CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) ☐
6		CITIZENSHIP OR PLACE OF ORGANIZATION United States

This Amendment No. 2 (“Amendment No. 2”) to Schedule 13D relates to the common stock, par value $0.0001 per share (the “Common Stock”) of Mandiant, Inc., a Delaware corporation (the “Issuer”), and amends and supplements the initial statement on Schedule 13D filed on December 21, 2020, as amended by Amendment No. 1 to Schedule 13D filed with the SEC on March 9, 2022 (as amended, the “Schedule 13D”). 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.

Item 4. Purpose of Transaction

Item 4 of the Schedule 13D is hereby supplemented as follows:

On September 12, 2022, pursuant to that certain Agreement and Plan of Merger, dated as of March 7, 2022 (the “Merger Agreement”), by and among the Issuer, Google LLC, a Delaware limited liability company (“Parent”), and Dupin Inc., a Delaware corporation and a wholly owned subsidiary of Parent (“Merger Sub”), the Issuer merged with and into Merger Sub (the “Merger”), with the Issuer surviving the Merger as a wholly owned subsidiary of Parent. In connection therewith, on September 12, 2022, immediately prior to the effective time of the Merger, 362,974 shares of Series A Preferred Stock held by Blackstone Delta Lower Holdings DE L.P. were converted into 22,767,802 shares of Common Stock and 7,026 shares of Series A Preferred Stock held by BTO FD Delta Holdings DE L.P. were converted into 440,710 shares of Common Stock. At the effective time of the Merger, each issued and outstanding share of Common Stock (other than certain excluded shares) was cancelled and extinguished and automatically converted into the right to receive $23.00 per share in cash, without interest and subject to applicable withholding tax. As a result, the Reporting Persons and the persons named on Schedule I no longer beneficially own any shares of Common Stock.

Item 5. Interest in Securities of the Issuer

Item 5 of the Schedule 13D is hereby amended and restated as follows:

(a) and (b) As of the date hereof, each of the Reporting Persons and the persons named on Schedule I does not beneficially own any shares of Common Stock.

(c) Except as set forth in this Schedule 13D, none of the Reporting Persons has effected any transaction in the past 60 days in shares of Common Stock.

(d) To the best knowledge of the Reporting Persons, except as set forth herein, no person other than the Reporting Persons has the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the securities beneficially owned by the Reporting Persons previously reported in this Item 5.

(e) On September 12, 2022, following the Merger, the Reporting Persons ceased to be the beneficial owner of more than five percent of the shares of Common Stock.

Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer

Item 6 of the Schedule 13D is hereby amended and supplemented by the following:

The information set forth or incorporated by reference in Item 4 is incorporated by reference in its entirety into this Item 6.

Upon the closing of the transactions contemplated by the Merger Agreement, the Merger Support Agreement was automatically terminated.

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.

Dated: September 14, 2022


BLACKSTONE DELTA LOWER HOLDINGS DE L.P.
By: Blackstone Delta Lower Holdings Manager L.L.C., its general partner

By:		/s/ Christopher J. James
Name: Christopher J. James Title: Authorized Signatory

BLACKSTONE DELTA LOWER HOLDINGS MANAGER L.L.C.

By:		/s/ Christopher J. James
Name: Christopher J. James Title: Authorized Signatory

BLACKSTONE DELTA HOLDINGS DE L.P.
By: BTO Holdings Manager L.L.C., its general partner

By:		/s/ Christopher J. James
Name: Christopher J. James
Title: Manager

BTO HOLDINGS MANAGER L.L.C.

By:		/s/ Christopher J. James
Name: Christopher J. James
Title: Manager

BLACKSTONE TACTICAL OPPORTUNITIES ASSOCIATES L.L.C.
By: BTOA L.L.C., its sole member

By:		/s/ Christopher J. James
Name: Christopher J. James
Title: Chief Operating Officer

BTOA L.L.C.

By:		/s/ Christopher J. James
Name: Christopher J. James
Title: Chief Operating Officer



BLACKSTONE HOLDINGS III L.P.
By: Blackstone Holdings III GP L.P., its general partner
By: Blackstone Holdings III GP Management
L.L.C., its general partner

By:		/s/ Tabea Hsi
Name: Tabea Hsi
Title: Senior Managing Director

BLACKSTONE HOLDINGS III GP L.P.
By: Blackstone Holdings III GP Management
L.L.C., its general partner

By:		/s/ Tabea Hsi
Name: Tabea Hsi
Title: Senior Managing Director

BLACKSTONE HOLDINGS III GP MANAGEMENT L.L.C.

By:		/s/ Tabea Hsi
Name: Tabea Hsi
Title: Senior Managing Director

BTO FD DELTA HOLDINGS DE L.P.
By: BTO FD Delta Holdings Manager L.L.C., its general partner

By:		/s/ Christopher J. James
Name: Christopher J. James Title: Authorized Signatory

BTO FD DELTA HOLDINGS MANAGER L.L.C.

By:		/s/ Christopher J. James
Name: Christopher J. James Title: Authorized Signatory

BLACKSTONE TACTICAL OPPORTUNITIES FUND – FD L.P.
By: Blackstone Tactical Opportunities Associates III – NQ L.P., its general partner
By: BTO DE GP – NQ L.L.C., its general partner

By:		/s/ Christopher J. James
Name: Christopher J. James
Title: Chief Operating Officer



BLACKSTONE TACTICAL OPPORTUNITIES ASSOCIATES III – NQ L.P.
By: BTO DE GP – NQ L.L.C., its general partner

By:		/s/ Christopher J. James
Name: Christopher J. James
Title: Chief Operating Officer

BTO DE GP – NQ L.L.C.

By:		/s/ Christopher J. James
Name: Christopher J. James
Title: Chief Operating Officer

BLACKSTONE HOLDINGS II L.P.
By: Blackstone Holdings I/II GP L.L.C., its general partner

By:		/s/ Tabea Hsi
Name: Tabea Hsi
Title: Senior Managing Director

BLACKSTONE HOLDINGS I/II GP L.L.C.

By:		/s/ Tabea Hsi
Name: Tabea Hsi
Title: Senior Managing Director

BLACKSTONE INC.

By:		/s/ Tabea Hsi
Name: Tabea Hsi
Title: Senior Managing Director

BLACKSTONE GROUP MANAGEMENT L.L.C.

By:		/s/ Tabea Hsi
Name: Tabea Hsi
Title: Senior Managing Director

STEPHEN A. SCHWARZMAN

/s/ Stephen A. Schwarzman

[Mandiant, Inc. – Schedule 13D/A]

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH

SOLE VOTING POWER

0

SHARED VOTING POWER

0

SOLE DISPOSITIVE POWER

0

SHARED DISPOSITIVE POWER

0

Mandiant, Inc. SC 13D/A