Trace the corporate ownership chain above a company and identify the natural persons who ultimately control it. RETURNS JSON with: ownership_chain (array of parent entities, each with name, relationship, jurisdiction and is_ubo_candidate), natural_persons (array of identified beneficial owners, each with name, nationality and natures_of_control such as "ownership-of-shares-75-to-100-percent"), lei of the subject entity, complexity ("SIMPLE", "COMPLEX" or "UNKNOWN"), data_confidence ("HIGH", "MEDIUM" or "LOW") and notes describing the chain depth found. SOURCES: GLEIF Relationship API for LEI parent-child records, Companies House PSC (People with Significant Control) Register for UK entities, and the OpenCorporates corporate network. USE WHEN beneficial-ownership disclosure is required under AML or KYC rules, or to detect ownership by a sanctioned parent. Called via MCP — usage is logged but not billed. For metered billing use the REST API with an API key.