West's Encyclopedia of American Law | Plagiarism

The act of appropriating the literary composition of another author, or excerpts, ideas, or passages therefrom, and passing the material off as one's own creation.

Plagiarism is theft of another person's writings or ideas. Generally, it occurs when someone steals expressions from another author's composition and makes them appear to be his own work. Plagiarism is not a legal term; however, it is often used in lawsuits. Courts recognize acts of plagiarism as violations of COPYRIGHT law, specifically as the theft of another person's INTELLECTUAL PROPERTY. Because copyright law allows a variety of creative works to be registered as the property of their owners, lawsuits alleging plagiarism can be based on the appropriation of any form of writing, music, and visual images.

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