A legal petition in the so-called "mystery case" that has been tied to special counsel Robert Mueller and involves a corporation owned by a foreign state has been posted.
You can read the filing here.
In the heavily redacted petition to the Supreme Court to hear the case the petitioner argues that the country where it is based is "immune from American criminal proceedings... because American courts have no subject-matter jurisdiction over criminal proceedings" against the country.
The petition says that the D.C Court of Appeals that ordered the corporation to hand over documents was the first court to ever do so.
"Country A explained that it is entitled under the FSIA to sovereign immunity from the subpoena and that American courts have no criminal jurisdiction over foreign states. The Government nevertheless demanded compliance with the subpoena," the filing says.