Enter into agreement to avoid idea theft

If Mary Poppins had been in the ad business she might have said, “A great idea is a thing of beauty and a joy forever.” Creative people are paid well for their ideas – new products, product names or concepts for advertising campaigns. These are all valuable commodities in the advertising and marketing world, and ideas are constantly being developed and disclosed. Yet how does one protect ideas? On the flip side, marketers and agencies often receive unsolicited (or solicited) ideas from individuals or companies. How does one avoid, or at least reduce the risk, of getting sued for allegedly using an idea improperly?