As of October 1st YouTube Creators can re-write copyrighted music in order to produce their own parody songs.
The changes gives Creators much more freedom without fear of legal repercussions and without the need to seek prior permission from the copyright owner.
Before this changes were made, anyone making a parody video in the UK, put themselves at risk of being sued by the copyright owner.
Copyright owners still have the right to take down the video if they feel the parody uses their material in a discriminatory manner. This puts the UK in line with other European countries where similiar laws exist which are similar to the US's fair use laws.