does an NDA expire if it has no end date.
An NDA carries 2 separate clocks, and people read the wrong one. One is how long the agreement is live and information passes under it. The other is how long the duty to keep quiet lasts after that.
If the second one is not written down, the duty is drafted to run indefinitely. What ends it in practice is usually the exceptions clause, not the calendar.
this page says what the words mean. it does not say what to do about them, and it is not legal advice.
where it turns up
mutual and one-way non-disclosure agreements, and the confidentiality section inside a contractor agreement or a statement of work.
the clause, as it usually reads
wording of the kind these documents carry. it is written for this page, not copied from anyone's contract.
6. Term
This Agreement shall commence on the Effective Date and continue for 2 years,
unless earlier terminated by either party on 30 days' written notice. The
obligations of confidentiality set out in Section 3 shall survive expiration or
termination of this Agreement and shall continue for so long as the
Confidential Information remains confidential.
line by line
the 2 years is the disclosure window, not the silence
The first sentence says how long the agreement is switched on. During those 2 years, anything either side hands over is covered by it.
Something disclosed in month 23 is protected. Something disclosed in month 25, after the agreement lapsed, is not covered by this agreement at all.
survive is the word that matters
Survival is what keeps the duty alive after the agreement itself is dead. Without a survival sentence, the duty ends with the agreement — which is the opposite of what most senders assume they signed.
Above, the duty survives with no fixed end: for so long as the information remains confidential. That is an indefinite obligation with a condition attached, not a perpetual one.
what actually ends the duty
The exceptions clause does the work. In standard wording, information stops being confidential once it is publicly known through no fault of the receiver. The same goes for information already known to them, developed independently without using it, or received lawfully from someone else free to share it.
So the duty ends piece by piece as each item falls into one of those buckets, rather than all at once on a date.
an indefinite duty is not automatically an unbreakable one
Trade secrets are ordinarily protected for as long as they stay secret, and NDAs are often written to keep that open-ended.
For ordinary business information, an indefinite duty has been challenged as unreasonable, and courts in some states have declined to enforce one on that basis. It depends on the state, the information, and the wording. So an NDA with no end date reads as a duty with no stated end rather than one guaranteed to last forever.
a required disclosure is not a breach
Most NDAs carry a line allowing disclosure compelled by law or by a court. It usually comes with a duty to tell the other side first, if that is permitted. That path stays open whatever the term says.
the wording that changes it
the same clause does very different things depending on which of these it carries.
- shall survive for 5 years following termination
- a hard stop. On the fifth anniversary the duty ends, whether or not the information is still secret.
- shall survive in perpetuity
- no end date at all, stated deliberately. Common for source code, formulas, and customer lists.
- 3 years, except for trade secrets, which shall survive for so long as they remain trade secrets
- 2 clocks by design: a short one for ordinary information, an open one for the crown jewels.
- no survival clause at all
- the duty is arguable once the agreement expires. This is the version people believe they signed and rarely did.
- This Agreement shall continue until terminated by either party
- the disclosure window itself has no end. It runs until somebody sends notice.
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documents this clause sits in
whole examples, with the summary sign writes for each one.
what a mutual NDA actually says · what a contractor agreement actually says
the other 8
what indemnify and hold harmless actually means · what joint and several liability means in a lease · can you cross out a clause before signing · how long you have to cancel after signing · what a personal guarantee means on a lease · what a binding arbitration clause means · what entire agreement means in a contract · what an automatic renewal clause means, and how to cancel