This is Planet Money from NPR.

In 1925, F. Scott Fitzgerald published The Great Gatsby.

And, like pretty much every author, he copyrighted the book when it came out.

Which, you know, fair enough, the way copyright worked at the time,

Fitzgerald and his heirs could collect royalties from the book for 56 years,

all the way until 1981.

And during that time, if anybody wanted to make a movie or a play or anything

at all based on Gatsby, they would have to get permission and probably pay a licensing fee to the Fitzgerald family.

And then, according to the law, after the 56 years,

the book would go into something called the public domain.

Fitzgerald's kids or grandkids wouldn't get royalties anymore.

And more importantly, anyone who wanted to could print up and give away copies of the book

or rewrite it from Tom's horse's point of view or create Gatsby on ice, anything at all.

And, you know, copyright is this balancing act.

On the one hand, you want to encourage and reward people who write books, who create things.

But you also want to let those things enter the public domain at some point.

So we can all share them and tweak them and build on them and make more creative stuff.

The artist is figuring out how long to keep something in copyright.

There was nothing special about 56 years. That's just a number that Congress picked.

And then, they decided to change it.

In 1976, just five years before the great Gatsby entered the public domain,

five years before Gatsby on ice, Congress changed copyright law.

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