There are 4 statutory "factors" that the law considers in determining whether a use is fair. It is by weighing each of these factors independently and then analyzing the results as a whole that you determine whether your use is "fair". This determination is never clear cut (unless you are sued and the courts tell you). So part of Fair Use analysis is also risk assessment. However, keep in mind that the courts do take into consideration your efforts to stay within copyright. Thus documenting your Fair Use analysis is always a good idea.
Factor 1: Purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes
Factor 2: Nature of the copyrighted work
Factor 3: Amount and substantiality of the portion used in relation to the copyrighted work as a whole
Factor 4: Effect of the use upon the potential market for or value of the copyrighted work
For Fair Use:
Against Fair Use:
For Fair Use:
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For Fair Use:
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For Fair Use:
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