This shows the shitty policy that most companies have. They use open source internally and give nothing back.
Yeah, I have been working for Rails shop that did exactly this. I wasn't able to do anything, not even in my spare time, to contribute to open-source projects or do other work. The other work I can understand, because I could help a competitor for an example. But that they owned ownership for every line of code written by me, even on my time off, was killing my inspiration.
Somehow, as if by magic, as soon as you become a freelancer people stop caring about butt-in-seat time and start caring about results. Same goes for IP, I have never had a client complain about opensourcing something I made on their buck.