Where'd you get the wrong idea that it was a Startup?
AngualrJS was a side project of Misko, who was working at Google on the DoubleClick team, until he bet he could rewrite DoubleClick in 1 or 2 (can't remember) weeks using his framework and cut down on the LOC/code complexity. He eventually did and they decided to go full time on the framework. They discussed this at the start of their Google IO presetation.
Notice the "Copyright 2009 - Angular / BRAT Tech. LLC" at the bottom of the page.
IIRC, They had a plan to provide a paid or freemium server-side counterpart. edit: freemium, see the first revision of getangular.com[2], there's a pricing tab which disappeared later on.
update 2: they were not acquired, they abandoned the startup because it did not get enough traction. The framework lived on, though.
Development history
AngularJS was originally developed in 2009 by Miško Hevery and Adam Abrons as the software behind an online JSON storage service, that would have been priced by the megabyte, for easy-to-make applications for the enterprise. This venture was located at the web domain "GetAngular.com", and had a few subscribers, before the two decided to abandon the business idea and release Angular as an open-source library.
Abrons left the project, but Hevery, who works at Google, continues to develop and maintain the library with fellow Google employees Igor Minár and Vojta Jína.[3]
I stand corrected, my apologies. I simply assumed that it was Misko's side project (by assuming, I mean made an ass of myself). I'm going to pay more attention next time they talk about its history to see if they actively attempt to not bring that part of its history up. Agree with novaleaf, it's super weird they never mentioned it.
AngualrJS was a side project of Misko, who was working at Google on the DoubleClick team, until he bet he could rewrite DoubleClick in 1 or 2 (can't remember) weeks using his framework and cut down on the LOC/code complexity. He eventually did and they decided to go full time on the framework. They discussed this at the start of their Google IO presetation.