The following retirements and releases have been confirmed.
We already knew about a couple of voluntary retirements, but there are more to report:
RHP Steve Martin - Drafted in the 37th round in 2011. Played last season at Greeneville. UPDATED TO ADD: As I was reminded in the comment below, this is why I was rooting for Steve Martin to make it (from August of 2011).
1B Justin Shults - Drafted in the 46th round in 2011. Played last season with the GCL Astros.
In addition, the following players were released:
RHP Ebert Rosario - Signed out of the Dominican Republic prior to the 2006 season. A converted position player, he played last season at Tri-City.
1B Jimmy Van Ostrand - Drafted in the 8th round in 2006. Played the last 4 seasons at Corpus Christi.
3B David Flores - Drafted in the 18th round in 2008. Split last season between Corpus Christi and Lancaster.
RHP Lance Pendleton - Re-signed as a free agent in November 2011 after pitching in 4 games in Houston in September.