Obama knew, he knew from the beginning. I would be thoroughly unsurprised to find out that he was in it from the initial planning stage.
How people have so quickly forgotten about those Stroak (sp?)/Page emails where Page typed, "POTUS wants to know everything we are doing." He was in on it from the beginning; and, since this meeting took place in the Oval Office, it would seem he was in at the beginning of the planning stage.