Also consider this with regard to other open source projects:
Proprietary PostgreSQL vendors often contribute a heck of a lot of source code back for a reason that seems obvious when you think about it and applies to something like Linux too. The basic issue is that if you keep your own private fork and maximize what's not shared then you also maximize the work you have integrating what everyone else is contributing. By giving back as much as you can, you cut your costs down the road. That isn't to say that EnterpriseDB gives back everything but they back quite a lot.
When it comes to a proprietary vendor like Microsoft, it is much harder to get the QA done, and get updated drivers out to customers.
Proprietary PostgreSQL vendors often contribute a heck of a lot of source code back for a reason that seems obvious when you think about it and applies to something like Linux too. The basic issue is that if you keep your own private fork and maximize what's not shared then you also maximize the work you have integrating what everyone else is contributing. By giving back as much as you can, you cut your costs down the road. That isn't to say that EnterpriseDB gives back everything but they back quite a lot.
When it comes to a proprietary vendor like Microsoft, it is much harder to get the QA done, and get updated drivers out to customers.