" Hi, it's me, your employer. Read your contract/employee handbook. Everything you do belongs to me. If I pay you a salary, I own you. Even if it's not in the handbook or contract, everything you do that's related to your basic job skills and my business belongs to me, even for hourly workers.
If you're an accountant you can probably paint portraits, but don't start a tax business on the side. I pay for those skills, 24/7; I own them. And any idea you come up with that's relatable to my business I own too. So that's my new day planner you're thinking about marketing.
Stay away from my market and my customers. Even if all you do is paint portraits, my clients are exactly that: mine. Do anything that competes or reflects poorly on my business (they met you here) and I'll own more than just your ideas and labor; I'll own your house, car and kids when my lawyers are done with you.
Best of luck in your new endeavor. "
Lifted from comments section of Lifehacker's article.