The register
The register lists Williams Murray Hamm in London as a licensed sponsor on Skilled Worker, an entry that goes back to at least 2026. Its rating on the register is Worker (A rating).
Williams Murray Hamm Limited is the registered name (Companies House number 03305951), a private limited company on the register since 1997. Registered office: 10 Dallington Street, London, EC1V 0DB, EC1V 0DB. Its filed activity puts it in professional and technical services. It has traded under other names before, including Williams Murray Banks Limited, Buttondome Limited.
A licence says an organisation may sponsor; it does not say it is hiring today. The way to find out is the same as for any employer: the careers page, the job boards, and a direct approach with a UK-style CV that says early that sponsorship would be needed.