While 99designs provides a standard NDA template that you can choose to use in a private contest, we are not party to the NDA, and we make no assurances as to its legality. Nor are we a legal service, so we cannot mediate disputes of this kind.
If ever you feel that an NDA you’ve signed has been breached, we recommend you seek assistance from a legal professional.
And, since we want to make sure our designers aren’t breaching our rules of conduct, please let us know too.