The perpetual trophy was presented and named the Alter Cup in 1986 in honor of Hobie Alter, Sr. and his extraordinary promotion of one-design multihull sailing and racing programs. In 2003 the event was renamed the Hobie Alter Cup. The Hobie Alter Cup has become one of the nation's major sailing championships, having featured world champions from numerous classes, Olympic medalists and several national champions from the multihull ranks.

The Multihull Championship was conceived by the Multihull Council in the spring of 1985 as a service to multihull racing sailors. It is intended to determine a U.S. national multihull champion and is sailed annually in various types of multihulls at various venues. Originally based on open Area eliminations, the committee decided to reinvigorate the championship by allocating spots to the major multihull classes in addition to the Area entries.

Source = US Sailing, hope this helps.