Utilize the input text as a context reference, choose the right relationship between Boeing and Seattle from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

Boeing's plan to set up a facility in China that would paint, finish and deliver 737 jetliners built at its factory near Seattle has provoked its largest union, representing about 35,000 Boeing employees.

Answer: location_of_formation