Copyright protects the original expression of ideas but copyright does NOT protect ideas.
There is currently a hot debate over a ‘Tiny Hat’ Saturday Night Live skit …where a comedy duo who had already produced a successful comedy skit about wearing ‘tiny hats’… is claiming that Saturday Night Live stole the ‘tiny hat comedy skit’ idea from them. Unfortunately for the comedy duo, copyright law doesn’t grant them the exclusive right to the ‘universe of all comedy skits about tiny hats’… just because they were the first produce a popular skit on the topic. Copyright law does, however, protect the dialogue and the video made of the comedy duo’s skit. And if either of these aspects of the skit are being copied, imitated, plagiarized, distributed or sampled without permission then copyright law can come to the rescue and battle the alleged infringer.
The IDEA of a skit about Tiny Hats isn’t protected by copyright law. (For example there are a lot of plays written about Star Crossed Lovers: Romeo and Juliet, West Side Story… etc) Here is a quote from the US Copyright Office website on what copyright protects: “Copyright does not protect ideas, concepts, systems, or methods of doing something. You may express your ideas in writing or drawings and claim copyright in your description, but be aware that copyright will not protect the idea itself as revealed in your written or artistic work.”
(…both Tiny Hat skits are pretty darn funny. Google ‘Battle of the Tiny Hat’ to take a look)
BY: Vanessa Kaster, Esq., LL.M.
vk@kasterlegal.com
See also: The U.S. Copyright Office website at http://copyright.gov/help/faq/faq-protect.html#idea, @iplegalfreebies and www.kasterlegal.com.
IP Legal Freebies Blog 
This is what makes IP work so interesting (and confusing). Was the dialogue copied or imitated in the SNL skit? I mean, how many times can you say something funny about wearing a tiny hat? This is why we need IP attorneys like you. Thank you!
If the actual dialogue had been copied or imitated.. then yes, a pretty solid copyright violation could be raised because this would be copying the ‘original expression of the idea’. However, in this issue over the Tiny Hat skits.. it’s just the theme that was copied. The dialogue wasn’t copied, the setting wasn’t copied, the characters weren’t copied… just the theme of ‘wearing tiny hats’ was copied. The IDEA of a skit about Tiny Hats isn’t protected by copyright law. (For example there are a lot of plays written about Star Crossed Lovers: Romeo and Juliet, West Side Story… etc)