The Ninth Circuit declined to block Judge Robart’s order on an emergency basis, although it has set a briefing schedule. As Dan notes below, the possibility of a 4-4 split on the Supreme Court means that the Ninth Circuit may effectively get the final say. Per Politico:
If the 9th Circuit declines to step in and block Robart’s order, the Justice Department could seek a stay from the Supreme Court. Such stay requests are usually referred to the full court, which has had only eight justices since the death last year of Antonin Scalia. That raises the prospect that the high court could deadlock, which would leave any 9th Circuit ruling in force.