In this comment, user253751 writes:

You cannot create derivative works without permission of the copyright holder (even if you create it and keep it to yourself)

really? That seems unconstitutional or something (in countries that have that). You should be allowed to do whatever you want with your own stuff in your own home.

Is the maker of the comment correct? Or is the quoted answer (by user gnasher729) correct? What is the US law on making derivative works?

4 Answers 4


The comment is incorrect; creating a derivative work without permission is still disallowed, even for private use.

In US copyright law 17USC 106 defines the exclusive rights that the copyright holder has, the right "to do and to authorize". The second of these is:

(2) to prepare derivative works based upon the copyrighted work;

Note that the right is the right to "prepare" a derivative work, not the right to "distribute" or "sell" the work.

US copyright law defines a derivative work in 17 USC 101 which reads:

A “derivative work” is a work based upon one or more preexisting works, such as a translation, musical arrangement, dramatization, fictionalization, motion picture version, sound recording, art reproduction, abridgment, condensation, or any other form in which a work may be recast, transformed, or adapted. A work consisting of editorial revisions, annotations, elaborations, or other modifications, which, as a whole, represent an original work of authorship, is a “derivative work”.

The laws of other countries are similar to US law on this point. Article 2, paragraph 3 of the Berne Copyright Convention provides that:

(3) Translations, adaptations, arrangements of music and other alterations of a literary or artistic work shall be protected as original works without prejudice to the copyright in the original work.

However, it should be noted that if a person creates a derivative work in private, and never shows it to anyone else, the copyright owner would never learn of it, and so could never sue for infringement. But if it were shown or described to anyone, and the owner did learn, then he owner could in theory sue. Whether the owner would choose to sue over a derivative work never circulated is a different matter.

The real effect of this law is that when an infringing derivative work is distributed and the owner wants to sue, the owner need not prove distribution. Proving creation of the derivative work is enough.

The quoted comment asks about whether such a rule is "unconstitutional or something" and says that "You should be allowed to do whatever you want with your own stuff in your own home."

The US constitution does not grant any such broad right. There are lots of things one might do in own's own home that are illegal: building a bomb for example.

Article I, Section 8, Clause 8 of the US Constitution, sometimes called the Copyright Clause or the IP clause, grants Congress the power:

To promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries.

See the LII page "Intellectual Property Clause" and the page Nature and Scope of the Right Secured for Copyright where it is written that:

Congress was within its powers in giving to authors the exclusive right to dramatize any of their works. Even as applied to pantomime dramatization by means of silent motion pictures, the act was sustained against the objection that it extended the copyright to ideas rather than to the words in which they were clothed. {Kalem Co. v. Harper Bros., 222 U.S. 55 (1911). For other problems arising because of technological and electronic advancement, see, e.g., Fortnightly Corp. v. United Artists Television, Inc., 392 U.S. 390 (1968); Sony Corp. v. Universal City Studios, 464 U.S. 417 (1984).}

See also the Wikipedia article "Copyright Clause".


The situation is not as clear-cut as David presents it in his answer.

The first thing to note is that derivative work, if lawful and creative enough, enjoys its separate copyright protection.

The second thing to note is that a derivative work is lawful when it constitutes "fair use". The relevant law is 17 U.S. Code § 107:

the fair use of a copyrighted work, including such use by reproduction [...] for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright.

(Emphasis by me.)

That statute lists a couple criteria to help determine fair use:

  • Is the use commercial?
  • What's its nature?
  • How much of the original work does it copy?
  • Does it diminish the potential market or value of the copied work?

As an example, a parody has been recognized as fair use. Quoting from an appeals court ruling in Keeling v. Hars :

While parody is not expressly mentioned in the statute, the Supreme Court has instructed that “parody, like other comment or criticism, may claim fair use under § 107.” Campbell, 510 U.S. at 579.

and further:

A close reading of the statute therefore makes plain that an unauthorized but lawful fair use employing preexisting copyrighted material may itself merit copyright protection.

The question of copyright protection for the derived work is only of interest here because granting the protection is only possible for a lawful copy. Which is the question here.

A plain, complete, non-artistic, non-commercial copy at home is a mixed bag. If it was made from an owned "original", like a software backup or a cassette taped from an album, it is not commercial and has zero economical impact. But on the other hand it reproduces the entire work, is neither criticism nor parody and is not used for teaching or the like.

In the end, this is a gray area in which there are no clear-cut demarcations.

From a systematic standpoint, it is always difficult to defend the prohibition of an act that does not hurt anybody, economically or otherwise: The law's primary function is to mediate conflicts of interest. That citizens are essentially free individuals is an idea of the Enlightenment which influenced the U.S. constitution, even if it is never explicitly expressed: Everybody can pursue their happiness after their own fashion, as long as they don't impinge on other people's rights.

Copyright exists so that I can't go and sell Mickey Mouse figures without a license, damaging Disney's business; but it is hard to justify that I cannot make a clay figure that looks like Mickey and put it on my mantelpiece.

The same argument has been made (unsuccessfully) for drug use at home, or (successfully) for consensual sex at home, even with the same sex.

As an aside, Germany appears to have a stronger protection for creative derivative works than the U.S. According to the German Wikipedia page on derivative works, derivative works are generally permitted even without the consent of the creator:

Die Bearbeitung eines Werkes ist grundsätzlich ohne die Zustimmung des Urhebers erlaubt.

  • 1
    "derivative work, if lawful and creative enough, enjoys its separate copyright protection": this fact is not relevant to the determination of whether a particular derivative work is lawful.
    – phoog
    Commented Dec 1, 2021 at 11:55
  • 1
    @phoog I mention it because it establishes the principle that a derivative work can have a separate copyright at all, which may not be obvious. This principle establishes the idea that a derivative work is an original creation potentially worthy of protection. The condition "lawful" is then discussed afterwards. Commented Dec 1, 2021 at 11:57
  • 2
    That's true, but I would also note that even in a lawful derivative work the owner of the copyright in the original work retains an ownership interest in the elements of the derivative work that derive from the original. A derivative work isn't wholly original, after all, by definition.
    – phoog
    Commented Dec 1, 2021 at 14:23
  • 1
    @grovkin "be more collaborative when they are uncertain whether their creations use others' IP too much": Indeed, see Weird Al Yankovich's stance. I mean, if his work is not parody, what is? Commented Dec 1, 2021 at 15:50
  • 1
    A copy made in your home that never leaves your home can be commercial and can diminish the value of the original. If everyone who wanted to use an expensive copyrighted software made a copy “to use at home”. They would be taking money from the owner if the copyright. Commented Dec 1, 2021 at 16:30

This is civil law.

A tort without damages is unenforceable.

There's no claim there. Your private derivative work, which you created and kept to yourself, does not create any opportunity venue in which the rights holder would be injured, and so there is no basis for money damages. There is no relief (damages) to grant.

The suit will be dismissed as "failure to state a claim on which relief can be granted".

  • You may have a point here, if we can believe the Wikipedia discussion about case or controversy. The juridical end result is very much in the vein of comment of user253751 ("You should be allowed to do whatever you want with your own stuff in your own home"): It will be hard to construe damage to the copyright owner, at least if the derivative work was made from a paid-for original. Extreme cases (an artist may not want to have a traumatic piece copied) may exist but many cases will not have standing, true. Commented Dec 2, 2021 at 7:34
  • From a systematic point of view I find it interesting that the basic "freedom to do what I want as long as I'm not hurting anybody", which should be the center and point of origin of individual rights granted by the constitution, is introduced through the backdoor of a regulation addressing the federal judiciary. Commented Dec 2, 2021 at 7:50
  • 1
    What about statutory damages? Also, if the copyright holder could have forced to you to buy a license, then the damages are the lost revenue from you not buying the license. Commented Dec 2, 2021 at 18:20

Yes - start a movement for masses of people to copy Disney movies in their home for personal use to watch and you will see no safe harbor for that copying.

  • 1
    There is in fact an ongoing debate regarding backup copies of legitimately owned works. If you copy something from the library though you are often hurting the copyright owner. Also, the debate is about derivative works. A more typical scenario for the question would be to record a karaoke of a pop song -- even from the library! -- or to transform Cinderella into a queer alien LSD fantasy in false color. Not to sell them, just for fun. Forbidden? Commented Dec 1, 2021 at 22:10

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .