Speculation that Adecco SA may buy USG People, one of the largest staffing firms in the Netherlands, prompted USG's stock to rise by as much as 5% in trading today, Reuters reported. Adecco is the world's largest staffing firm.

Separately, the world's third-largest staffing firm, Randstad Holding NV, plans to buy Vedior NV, the world's fourth-largest. Randstad and Vedior are also based in the Netherlands.