Thousand Oaks-based Amgen said Tuesday afternoon along with Boehringer Ingelheim, that the firm has agreed to sell rights in and substantially all of the assets of its Fremont, Calfiornia development and manufacturing facility. According to Amgen, it currently has 360 employees and 100,000 square feet of manufacturing space in the facility. The facility and employees will become part of Boehringer Ingelheim and its contract manufacturing business. Financial details of the sale were not announced. Amgen acquired the facility in 2006 when it acquired Abgenix.