If your idea is substantially different from theirs (yours being specific and theirs being vague), applying for your own patent, expressly including theirs as a

If your idea is substantially different from theirs (yours being specific and theirs being vague), applying for your own patent, expressly including theirs as a reference and distinguishing what's novel about your technology and how it differs from theirs, is probably the best way forward. Can't get much cheaper or more effective than having the USPTO rule your patent as valid and distinct; even a lengthy DIY patent process will run you less than a couple hours of a middling patent attorney's time. Odds are your business will fail or be acquired by the time the patent issues or even gets looked at (I'm still litigating a patent application I initially filed in 2010). Your goal is to succeed or fail based on the quality of your business model and only use the patent process as needed to entice investors and scare away trolls. Patent pending is not as good as issued, but darn close for a number of investors.