The register
The register lists Tsuruta Architects in London, Select a State/Province as a licensed sponsor on Skilled Worker, an entry that goes back to at least 2026. The register records its rating as Worker (A rating).
Companies House lists it as Tsuruta Architects Limited, number 05954816, incorporated 2006: 20 years of filings behind the name. The registered office is at Unit 9e Vanguard Court, 36-38 Peckham Road, London, SE5 8QT, SE5 8QT. Its filed activity puts it in professional and technical services.
Holding a licence is the expensive, slow part done. For Tsuruta Architects the question each time is only whether the role and the pay fit the current rules, and that is checked per vacancy.