At one stage trhere was an issue with this.
Someone was using the name of a company to remove videos under copy right claim, which the company did not have. further more when they investigated the issue they found the companys name was being used without their knowledge. There were rumours passed around that Korean fans were having the videos removed due to the links with the company being Korean. Crypton Future Media looked into it and there is no longer an issue.
However, before the issue was resolved a project called "Save Miku" was formed. Sadly in an effort to "Save Miku" many overseas fans uploaded copies of songs, leding to an increase in PV and music stealing (uploading without premission) on youtube and the project was changed to trying to educate people on uploading PVS and music without producers onsent instead.