You can read briefs and other filings at the SCOTUSblog case page. According to the Petition for Writ of Certiorari, the issues presented are:
1. Whether the President's recess-appointment power may be exercised during a recess that occurs within the session of the senate, or is instead limited to recesses that occur between enumerated sessions of the senate.
2. Whether the President's recess-appointment power may be exercised to fill vacancies that exist during a recess, or is instead limited to vacancies that first arose during that recess.Put another way: Under the Constitution, when can the President make the appointment, and when must the vacancy occur?
Per the Order, SCOTUS has also asked the parties to address:
In addition to the questions presented by the petition, the parties are directed to brief and argue the following question: Whether the President's recess-appointment power may be exercised when the Senate is convening every three days in pro forma sessions.I have been on this one for a while. Here's some background on the issue from my post of January 2012. And some Lawffice Links from the DC Circuit's decision that the appointments were unconstitutional. I find this issue fascinating, and it has the potential to impact recess appointments across presidents and agencies.
Image: Supreme Court seal. Not official use.