My point being, oversimplifying the issue by saying [pp] "I guess we don't own what's in our own heads" doesn't really move the discussion forward.
Don't know that we've ever enforced such an agreement, but it is in ink just in case it's needed.
Depending on where you live it might not even be enforceable. Even large companies will put employee agreements in front of you that they KNOW aren't enforceable in a particular state but will do it since they know that most people don't know any better.
I had a particular instance when a company I was working for got acquired by a Texas based company and they sent us the employee agreement they use in Texas to us in California. There were no less than 4 completely unenforceable clauses in that contract. And this was a public company doing this.
If you live in Texas, though, you're screwed.
I figure when it comes time for me to move on it'll have to be to a "safe harbour" state that views such agreements as unenforecable.
I'm not overly concerned about it regardless, as should I leave it wouldn't be to a direct competitor (or likely anyone that could possibly benefit from my industry-specific knowledge) - it'd be somewhere completely out of our industry. And if they want to make an issue over someone as small as me, then I'll just find a new line of work for a few years. There's no way they could claim a "training investment" or "trade secret protection" if I was a programmer and left to become a carpenter or a roughneck or somesuch.
I was working at a place for 4 years before they tried to get me to sign one. They said it was standard and wasn't enforceable anyways, and I pushed my point (why bother having me sign if its pointless) and they eventually dropped it. No agreement is better than potentially having to deal with an unenforceable one down the road.
I find it weird but it is understandable from a competition point of view. If it wasn't this way you would probably see a lot more eager competitive hiring for opposing companies in order to gain an edge.
Otherwise, expect to deal with this.