Initial screen by HR, then a screen by the potential manager (VP), later a full day interview on-site with 4 of the VPs of the team. 1st HR screen was straightforward and fair. 2nd one with the hiring team was also fairly straightforward, but required a bit more articulation for why the role, why would it be a good fit, etc. Final day was quite tough. Started with typical questions about background and experience but quickly turned into a fire drill interview. Rapid fire of why do you want to work here, what is your prior experience, what kind of projects have you worked on, then in strong detail explain every recommendation. As someone with a multitude of projects it's not always possible to remember everything in clear detail. Later on, it became, so now we hire you, how do we grow? - very open-ended, no context, no clarity, just a fire drill of an interview. Moreover, there was strong questioning on why the motivation for the role given relative short experience in current job when that could have been screened for during the 1st 2 rounds easily. Having been through a great multitude of case interviews with top firms, it was way too open-ended, without any material or information, and without adequate time or structure. Finally, be prepared for people that speak very quickly. Quite surprising to see in an OC based company.