The Supreme Court Monday declined to take up a sealed case from special counsel Robert Mueller’s investigation that sought to obtain information from a foreign government-owned company.

Little is known about the case, and most of the factual proceedings have been sealed or redacted. Even the country in question is not certain.

But according to briefs filed before the high court, the case involves a grand jury subpoena issued to a corporation that claims to be wholly owned by a foreign government. The company says that under the Foreign Sovereign Immunities Act of 1976, foreign governments are exempt from such subpoenas, and since the company is a subsidiary of the government, it should be exempt.

The federal district court in Washington, D.C. held the corporation in contempt for not complying with the subpoena, and the circuit appeals court in D.C. affirmed that ruling.

Without comment Monday, the Supreme Court declined to take up the appeal.

Court documents reveal a prosecutor from the special counsel’s office was handling the case, and the firm representing the foreign-owned corporation has represented Russian interests in the past, according to Politico.