WASHINGTON (Reuters) – Amazon.com Inc (AMZN.O) said on Monday its founder and Chief Executive Jeff Bezos is willing to testify to a congressional panel investigating potential violations of U.S. antitrust law by big technology companies.

The company confirmed a letter that its attorney sent to members of the House Judiciary Committee saying Amazon had cooperated with the probe. “This includes making Jeff Bezos available to testify at a hearing with the other CEOs this summer,” said the letter from Robert Kelner of Covington and Burling LLP.

The big four tech platforms — Alphabet Inc’s (GOOGL.O) Google, Apple Inc (AAPL.O), Amazon and Facebook Inc (FB.O) — are under investigation by a House Judiciary Committee panel and the U.S. Justice Department. The Federal Trade Commission is probing Facebook and Amazon and groups of U.S. state attorneys general are looking at Facebook and Google.

Kelner said in the letter that Amazon and the committee would need to “resolve a number of questions regarding timing, format, and outstanding document production issues, all necessarily framed by the extraordinary demands of the global pandemic.”

This would be the first time that Bezos has appeared before Congress, according to a source familiar with the company.

In early May, the committee wrote the Amazon.com CEO to demand his testimony in the wake of a report that the online retailer uses data from its third-party sellers to create competing products. Amazon’s associate general counsel, Nate Sutton, had denied under oath last July that Amazon used sensitive information from its independent sellers to develop Amazon products.

Further, the letter also noted that Amazon had given the committee’s antitrust panel more than 225,000 pages of documents and notes that the committee has not given a “binding commitment” that they would be confidential.