Facebook and its co-founder Mark Zuckerberg have been warned that they risk being sued by anyone from celebrities to ordinary citizens over one of the site’s most recognisable features – the ‘Like’ button. The site currently reveals any products or interests that users ‘like’ to their friends. This could be illegal under Californian law – which forbids unauthorised use of people’s likenesses for commercial purposes.. A judge in San Jose has thrown out the company’s bid to dismiss the first case against Facebook – where users allege they have been ‘economically injured’ by the site’s use of the ‘Like’ button for advertising.Facebook first introduced ‘promotions’ in January of this year – where users opt to ‘Like’ products, often in conjunction with prizes or even bonuses in online games -  with Zuckerberg insisting that ‘a trusted referral is the Holy Grail of advertising.’However, US District judge Lucy Koh has insisted that users should be entitled to some gain from commercial endorsements that stem if someone chooses to ‘like’ a certain product or interest on the site. Mail Online