The Pacific Maritime Association represents 29 ports on the West Coast.

Wikipedia says: "The principal business of the Pacific Maritime Association (PMA) is to negotiate and administer labor agreements with the International Longshore and Warehouse Union (ILWU). PMA’s 72 members are cargo carriers, terminal operators and stevedores that operate along the U.S. West Coast."

Their HQ is in San Francisco at 555 Market Street, Third Floor.