How long can an NDA bind you?
Every non-disclosure agreement makes two choices about time. The first is the contract's stated term — the number of years the obligation runs. The second is whether confidentiality survives the contract's end, and for how long.
These choices look procedural. They are not. They determine whether the obligation expires before you change jobs, before your company gets acquired, before the information stops being valuable — or whether it follows you the rest of your career.
U.S. courts have spent decades pulling at the edges of this question. The consensus that has emerged: trade secrets can be protected indefinitely; ordinary confidential information cannot. The middle ground is a wide reasonableness test that varies sharply by jurisdiction.
The default rule, and where it bends
Under standard contract law, parties can agree to whatever term they want — including no term at all. A perpetual NDA is not automatically unenforceable. What courts ask is whether the term is reasonable in light of the information being protected.
For trade secrets, perpetual protection is the default. The federal Defend Trade Secrets Act (DTSA) and state equivalents under the Uniform Trade Secrets Act protect information as long as it continues to derive economic value from being secret. An NDA that protects trade secrets indefinitely is consistent with that underlying right.
For everything else — pricing, customer lists, business plans, operational know-how — the default is far weaker. Courts in most U.S. jurisdictions apply a balancing test. They weigh the legitimate interest of the disclosing party against the burden on the recipient, with particular attention to whether the information has lost its competitive value over time.
Industry practice has settled at two to five years for general business NDAs. Mergers and acquisitions NDAs typically run three to five years. Employment NDAs vary more widely, but longer than seven years for non-trade-secret information starts to invite challenge.
What this looks like in real contracts
Three patterns appear in nearly every NDA we score. Recognize them and you can read the time obligation in seconds.
The survival clause is the one most signers miss. The contract may say "this agreement terminates on December 31, 2027" — and a survival clause buried in the boilerplate can extend specific obligations for years beyond that date.
Where perpetual NDAs lose
Five U.S. jurisdictions are particularly hostile to indefinite or perpetual confidentiality obligations for non-trade-secret information. These states either have statutes disfavoring perpetual restraints, or case law that has repeatedly refused to enforce them.
Why tech companies don't use perpetual NDAs
The most-cited modern data point comes from Silicon Image, Inc. v. Analogix Semiconductor, Inc., where Silicon Image discovered that the standard industry practice of using time-limited NDAs (two to four years was the norm) had inadvertently capped its ability to enforce confidentiality on trade-secret information.
The lesson the technology industry took from that case is bifurcated drafting. Most modern tech NDAs use a defined term (three to five years) for general confidential information, and a separate clause specifying that trade secrets remain protected indefinitely regardless of the general term. This pattern avoids both extremes — overreach that gets struck down, and under-protection that loses trade-secret status.
What NDASentry flags in this category
Three patterns under Term and Survival trigger findings in the NDASentry analyzer.
3.1 Perpetual or indefinite confidentiality
Open-ended terms ("in perpetuity," "indefinitely," or no stated term at all) trigger this finding. The risk is asymmetric: enforceable for trade-secret information, often unenforceable for everything else, but creating a chilling effect on the recipient regardless of the legal outcome.
3.2 Unusually long term (10+ years)
Stated terms of ten years or longer for non-trade-secret information sit well above industry norms and invite enforceability challenge. They also outlive most business relationships, meaning the recipient is bound long after the underlying engagement has ended.
3.3 Survival clauses extending obligations past termination
Survival clauses extend specific obligations beyond the contract's stated termination date. Common, often defensible, but easy to miss when signing — and frequently combined with perpetual language to produce de-facto indefinite obligations even when the headline term looks finite.
We are scoring a corpus of public NDAs to publish prevalence data for each pattern in this taxonomy. The findings — including what percentage of real NDAs contain perpetual confidentiality obligations, and how that varies by industry and jurisdiction — will appear here when the study is complete.