I have been attending Protospiel for almost a decade in the Ann Arbor area. It's less than a hundred designers in a ballroom. Most of them are seasoned enough that they know better than to talk about intellectual property. Then, three years ago, I attended my first Unpub in Baltimore. Every non-gamer I spoke to on that trip, upon finding out why I was there, immediately brought up non-disclosure agreements and intellectual property protection. This treats ideas as the important part.
Work, follow-through, and quality execution, is everything. As I said in a panel discussion at last year's Penguicon, a board game designer who thinks their idea is the valuable part will tend to give up when it gets boring. If you talk about an NDA in front of a publisher, you signal to them that you won't see it through.
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