So you're saying, I could take 98-99% of Jurassic park, alter 1 to 2% of it, using that 1-2% to ridicule the movie (maybe we could put a laugh track down and tell a dinosaur joke or two!) and release it in cinemas and I'd be home free using the parody fair use? That's about what this video did.
Maybe you're right, but I don't see argument holding water in court. Who knows?
Uhhh legally I guess you could. But it'll depend on what Judge you get.. because you'd be the first case of such a situation. The result of that case (if you even had the money to push it up the chain) could ratify exact percentage of a film one could pull from directly to use for a parody.
Also yes, you will most likely want to redo the soundtrack, as that's a separate copyright.
Fair Use is a straight forward law that people have a hard time accepting. Especially the creators of the original works.
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Here's another fun example of Fair Use.
If I had an assignment to share my inspirations and it was graded (both grade school and uni), I would legally be allowed to use video and music from anywhere and just create a montage and post it online.
Sure, montages aren't really that popular, but they are a very common thing people get YouTube strikes for and DMCA notices. Educational Fair Use is a way around that... the times it's actually usable is small though be most assignments don't ask such things haha.
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On another note... Have you seen an amateur level parody like that in a cinema before?... Movies by the Scary Movie dudes are the only parodies I've seen in theatres... and they completely recreate the works and mash a bunch together, a method that's sure to get a better payoff then your mentioned idea.