June 14 (Reuters) - The Longshore union and employers of 22,000 dockworkers at U.S. West Coast ports on Wednesday said they have reached a tentative deal on a new six-year contract, ending 13 months of talks and easing supply chain worries. "The tentative agreement delivers important stability for workers, for employers and for our country's supply chain," Su said in a statement on Wednesday. The tentative deal comes as retailers like Walmart (WMT.N) and Target (TGT.N) are starting to land merchandise for the critical back-to-school, Halloween and Christmas retail shopping seasons. Manufacturers, automakers and food producers who import or export goods also rely on the Pacific Coast ports. West Coast port market share dipped after some customers shifted cargo to rival East Coast and Gulf Coast ports to avoid potential labor disruptions during the negotiations.

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Persons: Julie Su, Joe Biden, Su, James McKenna, Willie Adams, Gene Seroka, Lisa Baertlein, Kanjyik Ghosh, Christopher Cushing, Michael Perry, Simon Cameron, Moore Organizations: ., U.S, Labor, Warehouse Union, Pacific Maritime Association, ILWU International, West Coast, Los Angeles, Walmart, Manufacturers, East, Port of Los Angeles, Twitter, Thomson Locations: . West Coast, San Francisco, California, Washington State, Long, United States, West Coast, East Coast, Gulf Coast, Panama, China, Port of, Los Angeles, Bengaluru