(adsbygoogle = window.adsbygoogle || []).push({}); 1976 1996 2002 2010 2013 Seattle Seahawks Expansion Per one of the agreed parts of the 1970 AFL-NFL Merger, the NFL began planning to expand from 26 to 28 teams. On June 15, 1972 Seattle Professional Football Inc., a group of Seattle business and community leaders started by Herman Sarkowsky and Ned Skinner, announced its …