Yes, investors will sign an NDA, but only in this specific circumstance

If you’ve tried to get an investor to sign a nondisclosure agreement (NDA) before you pitch them, you’ll often be waved off with something like, “We don’t do that.”
That is somewhat sensible: Investors talk to a lot of startups, so signing an NDA could open them up to liabilities in many ways. For example, an investor could agree to not share anything you’ve disclosed, but it’s possible they heard another startup doing exactly what you do, with exactly your approach a couple of weeks before they spoke to you. That puts them in an awkward position.
This practice is therefore so widespread it’s

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