I applied online. The process took 2 weeks. I interviewed at F5 (Seattle, WA) in Apr 2016
Interview
Round 1 - Phone conversation with product manager, nothing out of the box with him trying to better understand my qualifications and interests
Round 2 (On-site round) - Met/Interviewed with 5 people and the on-site process lasted for 3.5 hours (including a 1-hour lunch with the manager I interviewed with on phone)
Round 3 (Online hackerrank test) - A typical if you have given a similar one before. Keep a close tab on the time though. I couldn't complete mine.
Interview questions [1]
Question 1
Signed NDA, but be prepared to answer questions about your projects in more detail than ever before. Also, you can expect white-boarding for problems similar to the projects listed on your resume/CV. Basically, they want to see how honest you are on your resume and how well it fits into their requirements.