The Artistamp Artists Reunion & Philatelic EXposition was held on 10 November 2012 at University House in Seattle, Washington USA. Organized by Seattle artist C. T. Chew, AARPEX featured U.S. and Canadian creators of artistamps and mail art and was open to the public. Participant artists included Chew (Triangle Post), E. F. Higgins III (Doo Da Post), Anna Banana, Ed Varney, Dame Mailarta, Jas Felter, Steve Smith (Art Gone Postal), Harley, Jennie Hinchcliff (Red Letter Day), Robby Rudine (Dogfish of Tui Tui Post), Jack Lattemann (Cascadia Artpost), Dominique Johns (Bugpost), Teesha Moore, Bill Ritchie, Kathleen McHugh (Eagle Island Post), Dixion, Marvin Johnson (bufo), and Jere Smith. Jas Felter created a special "fireworks" artistamp and poster used in AARPEX publicity. On 11 November, AARPEX participants and friends participated in the grand opening of the Museum of Artistamps, hosted by Tui Tui Post.
Cascadia Artpost produced this slightly reformatted version of an AARPEX commemorative created for a composite sheet of stamps produced jointly by AARPEX participants and printed by Triangle Post. Sheets of the Cascadia Artpost AARPEX commemorative were specially delivered to AARPEX participants on the morning of the event.