I applied online. The process took 3 weeks. I interviewed at OpenX (New York, NY) in Apr 2016
Interview
The process had quick turn around. I heard back from HR a week after applying, had an interview with the recruiter then had 3 back to back interviews with every one on the team the following week. Heard back from the company about a week and a half after the final interviews.
Interview questions [1]
Question 1
Generic questions overall, be prepared to know about the competitors and company's products.