My patent lawyer told me to, but generally no. If I know the person ahead of time I just ask them to keep it to themselves. Plus I know VCs wont sign NDAs, but I would get someone to agree verbally to keep it to themselves.
Wouldn't it be better strategy to be as public as possible with this? To start a competitive situation where prospective acquirers would want to get to the tech first before their competitors?
Like Oculus did and got bought by FB.