Pay particular attention to amount and sustainability of portion used and the effect of use on potential markets
Fair use is the most significant limitation on the copyright holder's rights. Deciding whether the use of a work is fair IS NOT a science. There are no set guidelines that are universally accepted. Instead, the individual who wants to use a copyrighted work must weigh four factors:
The purpose and character of the use:
- Is the new work merely a copy of the original? If it is simply a copy, it is not as likely to be considered fair use.
- Does the new work offer something above and beyond the original? Does it transform the original work in some way? If the work is altered significantly, used for another purpose, appeals to a different audience, it is more likely to be considered fair use.
- Is the use of the copyrighted work for nonprofit or educational purposes? The use of copyrighted works for nonprofit or educational purposes is more likely to be considered fair use.
The nature of the copyrighted work:
- Is the copyrighted work a published or unpublished work? Unpublished works are less likely to be considered fair use.
- Is the copyrighted work out of print? If it is, it is more likely to be considered fair use.
- Is the work factual or artistic? The more a work tends toward artistic expression, the less likely it will be considered fair use.
The amount and substantiality of the portion used:
- The more you use, the less likely it will be considered fair use.
- Does the amount you use exceed reasonable expectation? If it approaches 50 per cent of the entire work, it is likely to be considered an unfair use of the copyrighted work.
- Is the particular portion used likely to adversely affect the author's economic gain? If you use the “heart” or “essence ” of a work, it is less likely your use will be considered fair use.
The effect of use on the potential market for the copyrighted work:
- The more the new work differs from the original, the less likely it will be considered an infringement.
- Does the work appeal to the same audience as the original? if the answer is yes, it will likely be considered an infringement.
- Does the new work contain anything original? If it does, it is more likely the use of the copyrighted material will be seen as fair use.
This is the factor that has changed how fair use is interpreted by publishers and by the courts. For example, the ability to easily find publishers addresses and copyright contact information on the internet, means that the "one semester without permission rule" is much more strongly enforced, and taken much more seriously by the courts. Another example, the ability to sell electronic copies of material over the internet means that publishers see almost any use as impinging on all potential markets.