Washington (CNN) A company with ties to President Donald Trump's brother was awarded a $33 million government contract earlier this year, and a rival bidder filed a complaint alleging potential favoritism in the bidding process, The Washington Post reported Saturday.

The government contract from the US Marshals Service went to the company CertiPath, which has been owned since 2013 by a firm with ties to Trump's younger brother, Robert Trump, the Post reports.

An anonymous rival bidder filed a complaint with the Justice Department's office of the inspector general claiming that CertiPath did not disclose "one of the President's closest living relatives stood to benefit financially from the transaction," according to a copy of the July 22 complaint letter obtained by the Post.

CertiPath, based in Reston, Virginia, specializes in digital security and verifying online identities, the Post reports, and the contract was to provide security for federal courthouses and cell blocks.

The complaint reads, according to the Post: "The circumstances of this contract award, and what appear to be CertiPath's efforts to obscure Mr. Robert Trump's financial interest in the company even as it trades on the Trump name, present the appearance of preferential treatment for those who are close to the President." The complaint was sent by the Washington law firm Venable on behalf of the client, the Post reports.

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