I'm an employee, so the "default" situation is copyright assigned to $WORK,

But regardless of the country you work in, it won't hurt to talk your legal department. You also may want to consider to have your company write a document that gives you permission to release the code - and to write down anything they expect you to do (or not to do).

But regardless of the country you work in, it won't hurt to talk your legal department.

I have found that talking to legal departments very often hurts in quite a few different ways, actually. YMMV. IANAL. HTH. TIA. kthxbi

It may hurt in the sense that they say "We're not going to allow you to do that" (but note that the OP already has permission from someone, probably his manager and maybe even people higher in the picking order). But that hurts less than when they say "You shouldn't have done that, and now we're going to fire/sue you".

Of course, the OP shouldn't just talk to the legal department on his own, and certainly not with the opening "I'd like to do this". He should bring his manager (or whoever gave permission) with him.