I'm not sure what you mean by "a private GitHub enterprise account", but GitHub has a product called "GitHub Enterprise", which is essentially GitHub in a VM th

I'm not sure what you mean by "a private GitHub enterprise account", but GitHub has a product called "GitHub Enterprise", which is essentially GitHub in a VM that you can install in your own data center. We have a lot fewer than 60 developers, and we have a GitHub Enterprise installation, partly out of concern about issues like this (and also maybe a little IP protection paranoia).