Yes it was Facebook who started the trend as early days of the Facebook platform trained many of the best growth hackers in the Valley. 'Dan Yue' at Playdom, 'Joe Greenstein' at Flixster, and 'David King' at (Lil) Green Patch were a few Facebook pioneers. But, it was 'Sean Ellis' (Eventbrite, Dropbox, Xobni, Catchfree) who Originally coined the term.

That's true hardly a few people are familiar with this job title outside SV. I myself being a startup addict from India came across this title one night and couldn't stop dreaming the very moment 'how to be a growth hacker*.