The JSON License: A Joke That Wasn't Funny¶

Lesson: Don't add humor to legal documents

What Happened¶

Douglas Crockford created JSON, the data format that powers most of the modern web. He also created a reference implementation and a small JavaScript library. He licensed it under a modified MIT license with one addition:¹

The Software shall be used for Good, not Evil.

Lawyers don't understand jokes. Legal documents aren't the place for personality. I've watched this lesson get learned the hard way more than once.

It was a joke. Crockford has said as much. A bit of whimsy in a legal document.

The problem: lawyers don't do whimsy.

Why It Matters¶

The clause is unenforceable... probably¶

What counts as "Evil"? Who decides? Is building surveillance software evil? Is building ad tech evil? Is building software for a government you disagree with evil?

No court has ruled on this clause. No one knows what it means legally. And that uncertainty is the problem.

Enterprise legal departments rejected it¶

Companies doing their due diligence saw the clause and flagged it. Not because they intended to do evil, but because:

The clause is ambiguous
Ambiguity creates legal risk
Legal departments minimize risk

IBM famously requested (and received) a license exception from Crockford.² Other companies just avoided the code entirely.

Major distributions excluded it¶

Debian and Fedora classified the JSON license as non-free.³ The "Good, not Evil" clause violates the Open Source Definition's requirement for no discrimination by field of endeavor.

From a strict reading, the JSON license isn't open source.

It caused actual work¶

Maintainers of projects that depended on Crockford's JSON library had to:

Replace the dependency with alternatives
Seek explicit license exceptions
Explain to their legal teams why a "Good, not Evil" clause existed

All because of a joke.

The Lesson¶

License text is legal text. Every word matters. Every clause has consequences. What seems like harmless whimsy to an author becomes a compliance headache for users.

If you want to be funny, write a blog post. If you want to license code, use a standard license and resist the urge to customize.

The JSON license is a permanent cautionary tale about mixing humor with legal documents. Crockford is a brilliant engineer. His license joke has caused more aggregate paperwork than most actual license disputes.

What To Do Instead¶

Use standard, OSI-approved licenses without modification
If you have opinions about how your software should be used, express them in documentation, not licenses
If you must add clauses, have a lawyer review them

The "Good, not Evil" clause accomplished nothing except creating work for people who wanted to use JSON parsing. That's not a good outcome for anyone.