I'm a university lecturer in Australia teaching mathematics. I produce question sheets for my students. It takes significant effort to produce high-quality questions. These question sheets are protected under copyright law. A US-based website allows students to post these sheets and pay for someone else to provide solutions which are then uploaded back to the website. The website appears to be based in California.
They provide a mechanism to take the sheets down by filing a copyright complaint. It can take a long time to be processed, by which time an answer can be uploaded and the cheating student sometimes gets a terrible solution, but sometimes gets a good solution. Once they have taken this down, the sheet is often re-uploaded.
In my current iteration, we are dealing with the 3rd round of takedown requests for the same material. It takes longer to make a decision about whether to take it down than it seems to take for the student(s) to reupload the questions afterwards.
What legal options do I have if this happens repeatedly? This company definitely has the technical sophistication required to ensure that material that has previously been taken down for copyright infringement cannot be reuploaded,