Reputation, in trademark law, refers to the level of recognition or goodwill that a trademark has acquired among the relevant consumer group or industry. A reputation can be built over time through extensive use and promotion of a trademark, resulting in a strong association between the trademark and the goods or services it represents. A trademark with a strong reputation is more likely to be recognized and remembered by consumers, and can be a valuable asset for a business.

Trademark reputation can be relevant in several aspects of trademark law, including trademark infringement and trademark dilution. In a trademark infringement case, a strong reputation can help establish that the trademark is well-known and that consumers are likely to be confused by a similar mark. In a trademark dilution case, a strong reputation can help establish that the unauthorized use of the mark is likely to dilute or tarnish its distinctiveness or reputation.

Trademark reputation can also be relevant in the context of opposition or cancellation proceedings, where a party may seek to prevent or cancel a trademark registration based on the mark's potential to cause confusion with an existing trademark or dilute its reputation. In such cases, evidence of a trademark's reputation and market recognition can be used to support the claim that the proposed mark is likely to cause confusion or dilution.