The register
The register lists RSMB Limited in London, England as a licensed sponsor on Skilled Worker, an entry that goes back to at least 2026. Rating on the current register: Worker (A rating).
At Companies House the business is Rsmb Limited (company number 02173860), a private limited company incorporated in 1987, 39 years ago. The registered office is at 77 Kingsway, London, WC2B 6SR, WC2B 6SR. By its SIC codes the business is in it, software and media. It has traded under other names before, including Rsmb Television Research Limited, Three Hundred and Thirty Third Shelf Trading Company Limited.
Holding a licence is the expensive, slow part done. For RSMB Limited the question each time is only whether the role and the pay fit the current rules, and that is checked per vacancy.