Fair Use provides guidelines, but very few hard and fast rules. As an example, sometimes using large amounts of a copyrighted work (perhaps even all of the copyrighted work) will qualify as a Fair Use, while sometimes using only a small amount of a copyrighted work will not qualify as Fair Use. As several cases show, the key is that all four of the factors must be considered.

 
icon for podpress  Standard Podcast [15:17m]: Play Now | Play in Popup | Download