Precisely copying a patent is not the only way that a business can infringe on a patent. Knowingly or unknowingly incorporating a patented invention or practicing or incorporating an invention sufficiently similar to a patented invention can also constitute infringement. A patent owner can enjoin your business from practicing the patent, and can sue for damages. In some situations, an injunction can be equally or more costly than potential damages, since it may mean legal fees, retooling costs, and inventory loss.

The only way to discover potentially blocking patents is to search the U.S. Patent and Trademark Office (PTO) database. Just because nothing like your business's product is on the market doesn't mean that it, or something too similar to it, isn't already patented. Although searching back twenty years is all that is needed to ensure that your business isn't infringing on a patent, it may be worth searching farther back. If an older patent exists covering all or part of the subject matter of your company's product, it is a good indicator that the component is safe to manufacture. If your company's product is truly novel, you may wish to consider applying for a patent.