Parody and satire are types of free speech that the First Amendment should protect. For each type of speech, enough has to be borrowed from the original to make the joke or criticism funny or biting.
Above, an example of a parody of Twitter, full example Twitter as It Really is here. The real name, logo and layout of Twitter is used, but the tweets and entries are faked.
The First Amendment protects free speech. The fair use provision of the Copyright Act 17 USC 107 is designed to resolve the tension between the First Amendment, which protects free speech, and the Copyright Act, which is designed to abridge certain forms of speech (i.e., there is no right to make the speeches of others).
One of the more interesting used of Twitter was the infamous Mayor Emanuel Twitter account:
As you can see, the parodist stole a political candidate's identity, adopted his trademark use of a certain four letter word, and achieved over 47,000 followers. Check out Mayor Emanuel here. The punk rock journalist who was the impersonator revealed here. Great analysis of the numbers relating the Mayor Emanuel here.
Good-natured winner Mayor Rahm Emanuel pledged $5,000 to his impersonator's charity of choice here.
Here is the text of 17 USC 107 in italics:
§ 107. Limitations on exclusive rights: Fair use40
Notwithstanding the provisions of sections 106 and 106A, the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use the factors to be considered shall include —
(1) the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;
(2) the nature of the copyrighted work;
(3) the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and
(4) the effect of the use upon the potential market for or value of the copyrighted work.
The fact that a work is unpublished shall not itself bar a finding of fair use if such finding is made upon consideration of all the above factors.
Courts analyze the four factors bolded above to test whether a use of someone else's copyrighted work is "fair use".
A definition of "parody" from Wikipedia:
A parody (pronounced /ˈpærədi/; also called send-up, spoof or lampoon), in contemporary usage, is a work created to mock, comment on, or make fun at an original work, its subject, author, style, or some other target, by means of humorous, satiric or ironic imitation. As the literary theorist Linda Hutcheon (2000: 7) puts it, "parody … is imitation, not always at the expense of the parodied text." Another critic, Simon Dentith (2000: 9), defines parody as "any cultural practice which provides a relatively polemical allusive imitation of another cultural production or practice." Often, the most satisfying element of a good parody is seeing others mistake it for the genuine article.
Parody may be found in music, art or culture, including literature, music (although "parody" in music has an earlier, somewhat different meaning than for other art forms), animation, gaming and cinema.
The writer and critic John Gross observes in his Oxford Book of Parodies, that parody seems to flourish on territory somewhere between pastiche ("a composition in another artist's manner, without satirical intent") and burlesque (which "fools around with the material of high literature and adapts it to low ends"). [1]
Wikipedia's definition of satire:
Satire is primarily a literary genre or form, although in practice it can also be found in the graphic and performing arts. In satire, vices, follies, abuses, and shortcomings are held up to ridicule, ideally with the intent of shaming individuals, and society itself, into improvement.[1] Although satire is usually meant to be funny, its greater purpose is often constructive social criticism, using wit as a weapon.
A common feature of satire is strong irony or sarcasm—"in satire, irony is militant"[2]—but parody, burlesque, exaggeration, juxtaposition, comparison, analogy, and double entendre are all frequently used in satirical speech and writing. This "militant" irony or sarcasm often professes to approve (or at least accept as natural) the very things the satirist wishes to attack.
Satire is nowadays found in many artistic forms of expression, including literature, plays, commentary, and media such as lyrics.
Courts, content owners and lawyers sending out cease and desist letters often do not appreciate the humor displayed by the would-be parodist or satirist.
The Chilling Effects website was created to catalog cease and desist letters sent to people by lawyers demanding that they cease infringing activity.
"Chilling effect" is a term of art from First Amendment case law referring to activities that "chill" free speech.
More on the fair use doctrine in copyright law here. Posts labeled "Fair Use Fridays" deal with problems and examples of conduct which may fall on either side of the fair use doctrine.
Virtually all commentators find case law interpreting the fair use doctrine to be subjective and problematic, some find it too restrictive, others find it too liberal, others find it arbitrary and incomprehensible.
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