Everyone here has already described most of the interview process accurately. A few comments that have not been mentioned. Because of the funding, there are over three thousand positions that are now being filled through several channels (Direct Hire events, rosters, etc). I selected that I didn't get an offer because I don't know. There is a 4-6 week backlog with HR. They now have to process all the decisions flowing in. While the managers may have informed HR of their decision within a week of the interview, HR is backlogged by the additional hires.