[rebootthesystem]

Well, if they are paying you to develop things and you do that at work, then they own it. That's what they pay you for.

On the other hand, whatever you do outside of work is another story. If you work on advertising and develop a pair of sunglasses for dogs --in other words, something completely unrelated-- it is unlikely there will be an issue.

However, if you develop something that is a derivative work of what you were paid to develop at work. You took a technology you were paid to develop and developed it further on your own time. Well, you better talk to an attorney.

On these matters I always ask engineers to place themselves in the shoes of the one paying the bills and the salaries. How would you like to pay a group of engineers really good salaries to develop something for you over, say, two years, and then have those engineers take that, evolve it on their own time and launch a competing business? You paid them for two years to both learn and develop a foundation they would not have had had they not worked for you.

Forget legal issues here. What are the moral and ethical issues related to taking something you got paid to develop for someone else, making it your own and then using it to compete against your former employer?

Talk to an attorney.