(Yicai Global) Feb. 14 -- The world's largest chemical producer BASF SE told unpaid migrant workers in Shanghai that it has no contractual or legal obligation to pay them after they demanded money from its local arm in a protest.

The laborers have no direct connection to BASF, but did work on the projects for the German firm's China unit, online news outlet Energy Yihao reported.

The staffers staged their protest on Feb. 8 at a bus station in China's largest city, calling for the company to pay construction fees and accusing it of falsifying legal evidence and refusing to comply with an arbitration decision.

"[The workers] claimed to be employees of a subcontractor of a contractor that worked on project by a BASF joint venture, and they asked us to pay them construction fees," BASF China said. "The contractor supplied steel structures but disputes arose after the agreement was implemented. Authorities have already made an arbitration ruling and our joint venture is working with the contractor so that both parties can comply with the decision."