I applied through an employee referral. The process took 2 months. I interviewed at Palantir Technologies (Palo Alto, CA) in July 2012
Interview
Their website describes the process well. I had a few phone interviews (with maybe 1-2 technical questions per call), and then was flown to their HQ in Palo Alto. You sign an NDA when you walk in, so I'm not sure how specific I can get but, as their site says, there is a series of technical interviews lasting ~45 minutes each. My questions mostly related to data structures and algorithms. Some were easy, others were challenging, but they are doable if you don't give up and ask for hints when you need them.
Interview questions [1]
Question 1
Modify existing data structure X so that it can also do Y.
Had a chat with HR and then a technical interview with an engineer. They gave some some quite normal leatcode type questions that I had to answer to continue to the next steps.
I interviewed at Palantir Technologies (New York, NY)
Interview
I have so far completed the 20 minute recruiter call, which was an easy behavioral. They asked me what I'm looking for in a job and what I do at my current role.
I applied online. The process took 4 weeks. I interviewed at Palantir Technologies (New York, NY)
Interview
Quick call with recruiter then technical interview. First call was easy, fit of company etc... Technical interview was leetcode easy and code walk through. Overall, much easier than what I had read online.