Another data point, but I worked for a company that made an expensive DSS for a very lucrative industry. We showed a potential "partner" our code and how it wor

Another data point, but I worked for a company that made an expensive DSS for a very lucrative industry. We showed a potential "partner" our code and how it worked and everything. They took our ideas and made their own product as a direct competitor. Reminded me of Apple and Xerox. Definitely get legal council involved. A possible way to protect yourself is print it out and put it in old fashioned binders and let them see the binder while you are watching. Not sure if that will fly, but it would be hard(er) for them to steal it. Tell the company your concerns (which are valid) and what methods they would accept. I don't think it's unreasonable for you to bring it up with them.