Are NDAs legally enforceable?

Yes, when they are reasonable. A court will enforce an NDA that clearly defines the confidential information, has a legitimate purpose, and lasts a sensible length of time. It will narrow or refuse to enforce one that tries to lock up everything forever, or that covers information already public or independently known.

What is the difference between a one-way and a mutual NDA?

A one-way NDA protects only one side's information, common when you disclose to a vendor or contractor. A mutual NDA protects both sides and is used when two companies share information to explore a deal. The protections are the same, just applied in one direction or both.

How long does an NDA last?

Whatever the contract says, commonly two to five years for ordinary business information. A true trade secret can be protected indefinitely, for as long as it stays secret. Carve-outs still apply throughout, so anything that becomes public or is independently developed falls out of the agreement regardless of the term.

What Is an NDA? Non-Disclosure Agreements Explained

A non-disclosure agreement, or NDA, is a contract in which one or both sides promise to keep shared information confidential. It is the everyday tool for protecting a trade secret before you reveal it.

An NDA, a non-disclosure agreement, is a contract where someone promises to keep your information secret and accepts consequences if they leak it. That is the whole idea. You are about to show a manufacturer your design, or an investor your numbers, and the NDA is what turns "please keep this quiet" into something a court can enforce.

It is the most common contract I see founders sign, and the one they read the least. Worth understanding.

Key takeaway: an NDA converts a casual promise of secrecy into an enforceable obligation. It is how you protect a trade secret before you hand it over, but a vague or overbroad one is barely worth the paper.

What an NDA does

It binds the receiver to use your confidential information only for an agreed purpose, and not to disclose it. Break that and you can sue for damages or for an injunction to stop further leaking. In practice it is the legal precondition for sharing anything you would not want a competitor to have.

One-way, mutual, and what is inside

A one-way NDA protects one side's information, you tell, they keep quiet, which is typical when you pitch a vendor. A mutual NDA protects both, used when two companies explore a deal and both reveal things. The mechanics are the same, the mutual one just runs both directions.

Inside, four clauses carry the weight: the definition of confidential information (too narrow, and the leak slips through the gap), the permitted purpose, the duration, and the carve-outs. Information that was already public, already known, or independently developed is never covered, and should not be.

What an NDA cannot do

It cannot protect what is not secret, once information is genuinely public, no NDA revives it. It cannot stop someone from independently inventing the same thing. And it does not give you a patent or a trademark, it only guards secrecy. Courts also trim or toss NDAs that try to lock up everything, forever.

What makes one actually hold up

Reasonableness. A definition tied to what is genuinely sensitive, a duration that fits the information (a few years for ordinary business data, indefinite for a true trade secret), and a real purpose. Courts enforce NDAs that are specific and refuse ones that overreach. Send a tight one, not a kitchen-sink one.

When you need one, and when you do not

Need it: before sharing designs, financials, customer lists, source code, or an unfiled invention. Skip it: pitching most VCs, who refuse to sign and it is not worth the fight, or for anything you are about to make public anyway. And remember that filing a patent eventually publishes it, so the NDA matters most before you file. A business or IP attorney can hand you a clean template, and you can compare them scored on Councl.