%0 Journal Article %T Substantial Similarity in Copyright Infringement: Emphasizing on US Case Law %J Public Law Researsh %I Allameh Tabataba’i University %Z 2345-6116 %A Zahedi, Mehdi %A sharifzadeh, shirin %D 2022 %\ 08/23/2022 %V 24 %N 75 %P 79-116 %! Substantial Similarity in Copyright Infringement: Emphasizing on US Case Law %K Substantial Similarity %K Copyright Infringement %K Idea and Expression %K Quadruple Tests %R 10.22054/qjpl.2021.59384.2581 %X Legal systems have taken different approaches to Copyright infringement but the ultimate purpose of them is to prevent the intentional and unjust appropriation of the rights of the creators. The proof of copyright infringement is easy when some rights such as reproduction is infringed or literal appropriation has taken place. However, it would be difficult to prove infringement when the plaintiff claims that defendant appropriated a material amount of his original work with some differences. The main question is how much similarities are too much? there is no definitive standard in the law, but courts believe that infringement occurs when the defendant’s work bears a substantial similarity to plaintiff's work and to achieve that they have introduced various tests. This article seeks to explain the concept of substantial similarity in Copyright infringement and the way to achieve it. The result of the research is the choice of one or more tests from the four available tests depending on the type and nature of the work. However, in all choices, it is necessary to separate protected from unprotected elements and dichotomy between idea and expression in the work. This article also show that qualitative similarities are more important than quantitative similarities. %U https://qjpl.atu.ac.ir/article_14593_fb56693d2a24cf1234deccf8f746fdfd.pdf