It is worth looking at the website of the Intellectual property Office for information about the law relating to trade marks and copyright.
Here are a couple of other interesting links about copyright in relation to photographs. Not strictly relevant but worth considering.
Are you Stealing Photographs? - top 10 lame responses - photography, copyright, social media & the internet Tony Bynum Photography
10 bogus excuses that people use when they steal a photo from the Internet / Photographer in Quebec city / Photographe à Québec