How does the fair use doctrine limit copyright protection?

The fair use doctrine serves as a legal defense against claims of copyright infringement, allowing for the use of protected material without the owner's permission under specific circumstances, such as criticism, scholarship, news reporting, and parody.1

Rather than being an absolute right, fair use acts as a limitation on copyright protection by balancing the rights of creators with the public interest. Courts determine whether a use is fair by evaluating four factors codified in the U.S. Copyright Act:1

• Purpose and character: Whether the use is transformative—meaning it adds new expression or meaning—is favored over simple reproduction.1
• Nature of the work: Factual works are more likely to be subject to fair use than highly creative works.1
• Amount and substantiality: Using smaller portions of a work is generally favored, though using the "heart" or most valuable part of a work may negate a fair use claim.1
• Market effect: If the reproduction competes directly with or serves as a substitute for the original, it is less likely to be considered fair.1