May 27 (Reuters) - The complete results of Exxon Mobil’s board of directors full voting results might not be known until next week, the company said on Thursday. Two seats on the 12-member board hang in the balance at Exxon following Wednesday’s annual general meeting, in which activist hedge fund Engine No. 1 gained at least two seats on the Exxon board. (Reporting by Jennifer Hiller Editing by Chris Reese) Our Standards: The Thomson Reuters Trust Principles.