The register
The register lists The Sigma Trust in Clacton on Sea, Essex 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).
Companies House lists it as The Sigma Trust, number 07926573, incorporated 2012: 14 years of filings behind the name. The registered office is at Clacton County High School, 51 Walton Road, Clacton On Sea, Essex, CO15 6DZ, CO15 6DZ. By its SIC codes the business is in education. It has traded under other names before, including Clacton County High School.
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.