Boeing Co. started talks with the International Association of Machinists and Aerospace Workers union to negotiate a new labor contract, the company announced on Friday.

The contract involves more than 26,000 workers in the Seattle, Portland, Ore., and Wichita, Kan., the Chicago-based company said.

It said a new contract with the IAM is anticipated to be in place by Sept. 4.

The company will negotiate new contracts later this year with the Society of Professional Engineering Employees in Aerospace, a union that represents more than 20,000 employees.

Shares of Boeing closed 0.83 percent down at $84.06 on the New York Stock Exchange on Friday.