A colour trade mark (British English) or color trademark (American English) is a non-conventional trade mark where at least one colour is used to perform the trade mark function of uniquely identifying the commercial origin of products or services. In recent times colours have been increasingly used as trade marks in the marketplace. However, it has traditionally been difficult to protect colours as trademarks through registration, as a colour as such was not considered to be a distinctive 'trademark'. This issue was addressed by the World Trade Organization Agreement on Trade-Related Aspects of Intellectual Property Rights, which broadened the legal definition of trademark to encompass "any sign...capable of distinguishing the goods or services of one undertaking from those of other undertakings" (article 15(1)). Despite the recognition which must be accorded to colour trade marks in most countries, the graphical representation of such marks sometimes constitutes a problem for trademark owners seeking to protect their marks, and different countries have different methods for dealing with this issue. This category of trade marks is distinguished from conventional (word or logo) trade marks that feature a specific colour or combination of colours; the latter category of trade marks present different legal issues. By jurisdiction India In India, a colour mark can be registered provided the consumers directly link the colour with the brand. The application might be refused if a single colour is claimed as it is difficult to prove distinctiveness with just a single colour. Australia Requirements are set out in the Trade Marks Office Manual of Practice and Procedure issued by IP Australia. European Union In the European Union, Article 4 of Council Regulation (EC) No. 40-94 of 20 December 1993 ("signs of which a Community Trade Mark may consist") relevantly states that any CTM may consist of "any signs capable of being represented graphically...provided that such signs are capable of distinguishing the goods or services of one undertaking from those of other undertakings". In Libertel Groep v Benelux Merkenbureau (case C-104/01) dated May 6, 2003 the ECJ repeats the criteria from Sieckmann v German Patent Office (case C-273/00) that graphical representation preferably means by images, lines or characters, and that the representation must be clear, precise, self-contained, easily accessible, intelligible, durable and objective. This definition generally encompasses colour marks, and therefore an applicant for a CTM or a national trademark in the EC may define their colour trademark using an