Also:
"under a corporate aegis"
Depending on how the company manages the open source project, this can strongly discourage community members. Even if the company TRIES to encourage community development, a combination of licensing and other behaviors of the company might cause issues.
See http://readwrite.com/2013/08/0... - I once saw another article (can't find link) where one of the MariaDB guys said that with the new org structure of MariaDB, they have FAR more community contributions than MySQL ever did, even before getting purchased by Oracle.
Another example was the Cyanogen Focal relicensing incident. Cyngn's founders tried to use their CLA to obtain MySQL-style dual licensing (and the founders cite MySQL's business model as their inspiration despite the fact MySQL never had a vibrant community behind it) caused a nasty forking event, and also caused other community projects in the AOSP-derivatives space to reduce their cooperation with CyanogenMod. I keep on hearing/seeing evidence that implies numerous people on the "community" side of things that stayed with the project are pretty unhappy, only staying because it's still (for now) the dominant and most well known project in that space. Cyngn leads have even found themselves having to bribe people with devices to get them to stay.
(Disclaimer: I was one of those who left CM after the Focal relicensing dispute.)