X0306 4 2022-09-12 1 0001370880 Mandiant, Inc. MNDT 0001206587 COVIELLO ARTHUR W JR C/O MANDIANT, INC. 11951 FREEDOM DRIVE, 6TH FLOOR RESTON VA 20190 1 0 0 0 Common Stock 2022-09-12 4 D 0 14292 23.00 D 0 D Common Stock 2022-09-12 4 D 0 12878 23.00 D 0 I See Footnote Common Stock 2022-09-12 4 D 0 28322 23.00 D 0 D Represents shares of the Issuer's common stock that were disposed of in connection with the merger of Dupin Inc. with and into the Issuer (the "Merger") pursuant to an Agreement and Plan of Merger, dated as of March 7, 2022, by and among the Issuer, Google LLC ("Google") and Dupin Inc. At the effective time of the Merger, each share of the Issuer's common stock was cancelled and converted into the right to receive $23.00 in cash. Shares held of record by the Arthur W. Coviello Jr. Revocable Trust, for which the Reporting Person serves as a trustee. At the effective time of the merger, each outstanding restricted stock unit ("RSU") was canceled and converted into a right to receive an amount in cash equal to the product of (1) $23.00 and (2) the total number of shares of the Issuer's common stock then-subject to such RSU. Richard Meamber, Attorney-in-Fact 2022-09-12