Atreca Manager interview questions

Applied 1 month prior to phone interview, 1 month later scheduled for on-site interview. 9:00AM - 4:00PM, met with 13 people, each for 30 minutes (3 for lunch). This is a very long day. All in one room. One month later I got a verbal offer. I Politely negotiated salary and title. The hiring manager told me that HR would have to be consulted. No communication for 3 days. Upon my follow-up with HR, the offer was retracted.