From Ballot Access News on December 18, 2019:
The Fourth Circuit will hear Johnston v Lamone, 19-1783, on Thursday, January 29, 2020. This is the case on whether it is constitutional for Maryland to force the Libertarian Party to submit 10,000 signatures in order to get back on the ballot, even though the party has approximately 22,000 registered members. The party argues that the petition is meaningless because it is obvious that there are at least 10,000 voters who want the party on the ballot; otherwise they wouldn’t remain registered members. The U.S. District Court had upheld the law.