Patent Trolls Sitting Under The UX Bridge: How the U.S. patent system may affect your everyday UX work:
"The reality is that generic elements of digital interfaces or parts of websites are in fact owned by various corporate entities and some of these entities have no intention of commercializing them within their own products. Simple functions within UX design as basic as menu systems and “upgrade” buttons are patented. These patents cannot be freely used by the people who don’t own them. I am sure almost every UX designer has unknowingly infringed upon a U.S. patent."