From my experience in large (and small) companies, trying to get something that is internally dead open sourced is usually not a huge fight against people saying no, just a laundry-list of things that need to be done before everyone will sign off on it.
One motivated person at a decently high enough level can get it pushed through, as long as whoever the person making the decision asks about it says, 'eh, ok.'
> Instead, we took a more direct route - I asked friends at Google (which bought Fitbit, which had bought Pebble’s IP) if they could open source PebbleOS. They said yes! Over the last year, a team inside Google (including some amazing ex-Pebblers turned Googlers) has been working on this. And today is the day - the source code for PebbleOS is now available at github.com/google/pebble (see their blog post).
One motivated person at a decently high enough level can get it pushed through, as long as whoever the person making the decision asks about it says, 'eh, ok.'