Youtube Copyright Claims?
A mashup puts together different copyright materials in a creative and transformative way, and Falzone says that mashups generally present interesting fair use questions. They are definitely transformative. However, the content used in mashups is also usually highly creative and some copyright owners have been pretty aggressive about going after people for using content in this way. However, more and more copyright owners are leaving this type of content up because it is free promotion for the original and YouTube has given them ways to monetize this content. But again, if you’ve got any questions then definitely consult a lawyer