Microsoft Corp. and Yahoo Inc. have received the green light from U.S. and European antitrust officials to move forward with their search advertisement partnership, which is intended to take on search engine leader Google Inc., without imposing any restrictions. The 10-year partnership will allow Microsoft to power Yahoo’s search engine, while Yahoo will become the exclusive worldwide relationship sales force for both companies’ premium search advertisers. Microsoft will keep 12 percent of the search revenue generated on Yahoo’s and its partners’ Web sites during the first five years of the deal and will pay 88 percent to Yahoo as a traffic acquisition cost. The companies hope to transition U.S. advertisers and publishers before the holiday season, and all global customers and partners by early 2012.