(CNN) – A foreign company that has remained unnamed in legal proceedings is now appealing a subpoena from special counsel Robert Mueller to the Supreme Court.
The case, which has been shrouded in secrecy, is the first known legal challenge related to Mueller to reach the Supreme Court.
The company, understood to be owned by the government of a foreign country, has been subpoenaed by the special counsel for unknown reasons.
The subpoena is only known to compel the company to provide information about its operations for a criminal investigation.
It has fought that subpoena in court. However, it lost a federal appeals court decision that said it must comply.
The company is now asking the justices of the nation’s highest court to stay that ruling, and allow it to circumvent the grand jury subpoena by Mueller’s office.
In another potential first, if the Supreme Court takes up the case and leaves it under seal, it would be the first case before the court conducted entirely in secret, legal experts said.