A total of 6,550 members of the United Steelworkers union (USW) at 15 plants, including the 12 refineries, are involved in the work stoppage that began on Feb. 1 when talks for a new three-year contract between the USW and lead oil company negotiator Shell Oil Co stopped. After the latest breakdown between the two sides, Steelworkers leaders targeted Shell, which is the U.S. arm of Royal Dutch Shell Plc, calling workers out at a chemical plant and three refineries in the company’s Motiva Enterprises [MOTIV.UL] joint-venture with Saudi Aramco [SDABO.UL].