1) The copyright holder has to enforce their copyright against infringers – Copyright law and trademark law are often mixed up. Copyright holders have to enforce their copyright themselves in order to their copyright to be upheld. Many copyright holders turn a blind eye when it comes to fan works because it does nothing to hurt their copyright.
2) Big companies are bullies for enforcing trademarks against small time copyright infringers – The difference between a copyright and a trademark is that trademark holders have to enforce their trademark or else they might lose their trademark. Thus, these companies must enforce their trademarks against whoever might infringe upon it.
3) It is always illegal to sell fan art – There are four factors when determining whether or not something falls under fair use of an existing copyright. Each factor has to do with the nature of the use and whether it will be used for commercial or non-profit purposes. Under parody law, you can 100% sell fan work if it is a parody of the original.
4) It is fair use if I’m not selling the copyrighted material – It is illegal to create multiple copies of copyrighted material and give it out for free. Although you might not be selling the material for money, this still falls under unfair use of copyrighted material and is against the law.
5) Trademark holders have to have invented the trademarked material – The purpose of a trademark is to protect a business’ ability to create a brand without consumer confusion. Patent law protects the invented material.