Had 3 rounds, 1st round interview was with engineering lead asked mostly my background, 2nd round was with team of engineer, around 3-5 senior/staff engineers. Round 3 was design challenge, instructions were unclear/open for interpretation, didn't even give me a chance to explain/talk through my design.

Though very long, the interview panel was pleasant, asked fair questions and answered questions thoroughly. I was able to speak with people from many different parts of the organization including technicians, engineers, and director level executives.