AdTheorent Holding Company, Inc.

MCAP Acquisition Corporation (the “Company”) was unable, without unreasonable effort or expense, to file its Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2021 (the “Quarterly Report”) by the prescribed due date for the reasons described below. As a result of recent guidance to Special Purpose Acquisition Companies by the U.S. Securities and Exchange Commission regarding redeemable equity instruments, the Company revisited its application of ASC 480-10-S99 on its financial statements. The Company had previously classified a portion of its Class A common stock in permanent equity. In accordance with ASC 480-10-S99 and after discussion with the Company’s management, the Company’s audit committee concluded that all of its Class A common stock should be classified as temporary equity. The Company is working diligently to complete the review of the financial statements for the three months ended September 30, 2021 as soon as possible; however, given the scope of the process for determining the appropriate treatment of the redeemable equity in accordance with ASC 480-10-S99, the Company is unable to complete and file the Q3 2021 Form 10-Q by the required due date of November 15, 2021 without unreasonable effort and expense. The Company does, however, expect to file such report within five calendar days thereof. 2

MCAP Acquisition Corporation (the “Company”) was unable, without unreasonable effort or expense, to file its Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2021 (the “Quarterly Report”) by the prescribed due date for the reasons described below. As previously disclosed, in light of the Staff Statement on Accounting and Reporting Considerations for Warrants Issued by Special Purpose Acquisition Companies (“SPACs”) (the “Staff Statement”) issued on April 12, 2021 by the staff of the Securities and Exchange Commission, on May 12, 2021, the audit committee of the Company’s board of directors, together with management, determined that the Company’s audited balance sheet as of March 2, 2021, filed as an exhibit to its Current Report on Form 8-K filed on March 8, 2021 (the “Original Financial Statement”), should be restated. The Company’s financial statements for the three months ended March 31, 2021 cannot be finalized until the restatement of the Original Financial Statement is completed, after which time the Company intends to file the Quarterly Report with the SEC within five calendar days of the prescribed due date. 2