Washington (CNN) The defendant in the mystery grand jury subpoena challenge related to the Mueller investigation is being represented by the law firm Alston & Bird, a firm that has previously represented Russian entities, a lawyer working to unseal the case confirmed Wednesday.

Ted Boutrous, the lawyer for the Reporters Committee, confirmed CNN's prior reporting that Alston & Bird represents the foreign government-owned company facing scrutiny from special counsel Robert Mueller.

That subpoena case is now before the Supreme Court, and Boutrous' team is attempting to get parts of it unsealed.

Boutrous said in a statement that the government revealed Alston & Bird's identity during legal proceedings, and that they "did not object to the government's disclosure originally, and neither party has suggested to us in their emails or otherwise that we need to keep counsel's identity a secret."

"Given these circumstances, we believe that there are no restrictions on us and that it is appropriate for us to confirm that, based on the events described above, the identity of Petitioner's counsel in the Supreme Court is Brian Boone of Alston & Bird," he added.

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