3 rounds of interviews, Two phone, one on site. First one was with a HR, she asked a few easy quant questions and some HR stuff. Massively screwed up the HR Qs but still got 2nd round as I crushed the quant questions. 2nd round much harder. Really tricky game theory and probability questions with a trader, no HR. 3rd round, with head of desk and a HR girl, more game theory, easier than 2nd round. Some HR Qs, they seemed to not be important though.

First round was a phone interview, pretty easy probability questions. Second round was a phone interview. Again, pretty easy probability questions, but I fumbled on the last one. Had three questions the first round, and second round had two questions.

Applied on website - received first-round phone interview within a few weeks. First interview was why trading/why SIG, if I played poker, and probability/math questions for 30 minutes. Very straightforward - what's the expectation of a dice roll, what's the expectation if you get to re-roll, what about a call option on this game. Bayes' formula. Second round was a harder iteration of the first but still straightforward and easy. They will help you if you ask for hints. Final round - flew me out to Philadelphia and put me in a 4-star hotel - all expenses paid. Shadowed two traders to gauge interest in the firm, then an individual interview that is a harder iteration of the first two phone interviews. And a group interview to see how you work in a team environment.