Let’s watch them all in reverse chronological order of CEO-ship. 
1. Satya Nadella (CEO – Feb 2014 to present)
Satya Nadella doing it for ALS
2. Steve Ballmer (CEO – Jan 2000 to Feb 2014)
Steve Ballmer taking the bucket
3. Bill Gates (Founder and CEO, 1975 until 2006)
Bill Gates invents an ice bucket machine
