It's not that you can't build it, it's not that it's not Open Source, but it's still PR, here's why. I'll use the comparison of Fedora and Red Hat Enterprise,

It's not that you can't build it, it's not that it's not Open Source, but it's still PR, here's why. I'll use the comparison of Fedora and Red Hat Enterprise, or openSuse and Suse. These are truly open source. If you are going to base your proprietary technology on an Open Source project, please build the Open Source version and distribute it if you are building the Proprietary one, otherwise, you don't want people to actually use the Open Source version, it just means you have a good PR consultant and you don't mind "free help". I bet you $100 they got the idea from a focus group, and Google Chrome has things that Chromium doesn't.