Material Event (Form 8-K)

As previously disclosed, on July 29, 2026, MarketAxess Holdings Inc. ("MarketAxess") entered into an Agreement and Plan of Merger with Intercontinental Exchange, Inc. ("Parent") and Igloo Merger Sub II, Inc. ("Merger Sub"), providing for the merger of Merger Sub with and into MarketAxess (the "Merger"), with MarketAxess surviving as a wholly owned subsidiary of Parent.

The Merger is conditioned on, among other things, the expiration or early termination of the statutory waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the "HSR Act"), and other required regulatory approvals.

On October 21, 2026, the Department of Justice and the Federal Trade Commission granted early termination of the waiting period under the HSR Act effective as of October 21, 2026, satisfying the HSR Act condition to close the Merger.

The Merger remains subject to the remaining customary closing conditions and approvals, including approval by the stockholders of MarketAxess and the receipt of other required regulatory approvals.

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