After a short conversation with a recruiter, I was sent a 45 minute timed single-question coding challenge. Had I passed that a short conversation with the hiring manager would have followed, and then a ~4hr set of panels on site. While I won't discuss the specific question on the coding challenge, it required knowing or re-inventing an obscure and reasonably complex algorithm. While it's possible that most CS degree programs would have included the algorithm in question, mine did not, and even if it had I would not have remembered it 7+ years later. If anything, I think the test mostly selects for people willing to violate the closed-book element of the challenge. I would not suggest applying to Apex Clearing for a technical role unless you're willing to break their rules or they revise their hiring process.