<Li> Amount and substantiality of the portion used in relation to the copyrighted work as a whole: Courts look at both the quantity and quality of the copyrighted material that was used . Using a large portion of the copyrighted work is less likely to be fair use . However, courts have occasionally found use of an entire work to be fair use, and in other contexts, using even a small amount of a copyrighted work was determined not to be fair use because the selection was an important part--or the "heart"--of the work . </Li> <Li> Effect of the use upon the potential market for or value of the copyrighted work: Here, courts review whether, and to what extent, the unlicensed use harms the existing or future market for the copyright owner's original work . In assessing this factor, courts consider whether the use is hurting the current market for the original work (for example, by displacing sales of the original) and / or whether the use could cause substantial harm if it were to become widespread . </Li> <P> In addition to these four factors, the statute also allows courts to consider any other factors that may be relevant to the fair use analysis . Courts evaluate fair use claims on a case - by - case basis, and the outcome of any given case depends on the specific facts of that case . There is no formula to ensure that a predetermined percentage or amount of a work--or specific number of words, lines, pages, copies--may be used without permission . </P> <P> The justification of the fair use doctrine turns primarily on whether, and to what extent, the challenged use is transformative . "The use must be productive and must employ the quoted matter in a different manner or for a different purpose from the original . A quotation of copyrighted material that merely repackages or republishes the original is unlikely to pass the test...If, on the other hand, the secondary use adds value to the original--if the quoted matter is used as raw material, transformed in the creation of new information, new aesthetics, new insights and understandings--this is the very type of activity that the fair use doctrine intends to protect for the enrichment of society ." </P>

Copyright law in the united states applies to which type of resources