All YouTube users can upload videos up to 15 minutes each in duration. Users who have a good track record of complying with the site's Community Guidelines may be offered the ability to upload videos up to 12 hours in length, which requires verifying the account, normally through a mobile phone. When YouTube was launched in 2005, it was possible to upload long videos, but a ten-minute limit was introduced in March 2006 after YouTube found that the majority of videos exceeding this length were unauthorized uploads of television shows and films. The 10-minute limit was increased to 15 minutes in July 2010. If an up-to-date browser version is used, videos greater than 20 GB can be uploaded.
Try to answer this question if possible (otherwise reply "unanswerable"): in 2006 Youtube found that the majority of longer videos were what?
unauthorized uploads