Here’s an excerpt from this piece about what current practices exist for non-disclosure agreements:
To understand current market practice on these issues, we surveyed agreements dated between January 1, 2014 and December 31, 2015. We found 66 examples in Securities and Exchange Commission filings, including 31 mutual and 35 unilateral NDAs. Delaware law governed sixty-two percent of the agreements, and an additional 20% were written under New York law. The most common agreement term was two years (40%). One agreement remained in effect for five years, (the longest term), and two for only six months (the shortest). Ten agreements (15%) did not specify a termination date, implying a perpetual term, and six others provided for presumptively perpetual survival of the agreement’s confidentiality provisions.