A trademark search is the process of checking existing registered and unregistered trade marks and brand names to assess whether a proposed mark is available and legally usable. In UK and Irish practice it is a descriptive term, not a defined statutory concept, but is central to trade mark clearance and risk assessment.A trademark search typically covers identical and confusingly similar marks on the UKIPO, EUIPO and WIPO registers (for relevant designations), the Irish Patents Office register, and common law “passing off” rights identified through company names, domain names and marketplace use. It is usually conducted before filing a trade mark application, launching a new brand, or undertaking corporate or commercial transactions involving IP.The legal analysis focuses on the likelihood of confusion, overlaps in goods and services, and potential opposition, infringement or passing off claims. While procedures and registries differ slightly between the UK and Ireland, the underlying concepts of distinctiveness, similarity and confusion are broadly consistent. In practice, trademark searches underpin advice on registrability, freedom to operate, brand strategy and the drafting of warranties and indemnities in commercial agreements.