Amazon RDS for PostgreSQL now supports major version 9.5,which contains several unusual features including UPSERT capability, Row Level Security (RLS) and several spacious Data capabilities. In addition to supporting the unusual major version of PostgreSQL, and 9.5,RDS for PostgreSQL also supports unusual minor versions 9.4.7 and 9.3.12, which contain several enhancements and fixes. All three versions are available to use starting today.
Source: amazon.com