Canadian trademark law provides protection to marks by statute under the Trademarks Act and also at common law. Trademark law provides protection for distinctive marks, certification marks, distinguishing guises, and proposed marks against those who appropriate the goodwill of the mark or create confusion between different vendors' goods or services. A mark can be protected either as a registered trademark under the Act or can alternately be protected by a common law action in passing off. Overview The scope of Canadian trademarks law A trademark is only protected to the extent that it is used by a person to distinguish a product or service from another. Trademarks do not give exclusive rights to a symbol, for instance, but only for the symbol in relation to a particular use in order to distinguish the product from others. Trademarks help potential customers to identify the source of products and thus have a significant impact on trade, especially when product identity is marketed as an extension of the customers' personal identity. Although any name or symbol could be protected under trademark law, there are issues concerning the limits of that protection. For instance, enforcing protection of a mark and its perception is questionable where there is no actual confusion for consumers. Likewise, protecting a mark against all criticism or allusions, as if it were an actual person, is controversial since trying to protect marks at all costs could be harmful to free speech and free trade. Statutory definition of trademarks in Canadian law The Act gives the following definition for the scope of trademarks: Certification marks are used in classifying the nature of a good or service (e.g., a Fair Trade Certified logo). A distinguishing guise can only be registered if it "is not likely unreasonably to limit the development of any art or industry". In Kirkbi AG v. Ritvik Holdings Inc., the Supreme Court of Canada declared: Kirkbi clarifies that the mere purpose of a product, however unique, cannot be subject of a trademark. Such utilitarian features fall more properly within the realm of patent law. The distinct look and feel of a product, however, can attract trademark protection. In Ciba-Geigy, the Supreme Court of Canada held that trademark infringement had occurred when the size, shape, and colour of Metoprolol tablets (used to treat hypertension) were mimicked by two competitors with comparable products. Canada, unlike the US, does not have a provision