Version 2.0, 16 September 2026. Start with the main SOLT member-venue list: 47 named entries. Exclude nine producing/subsidised institutional venues, retaining 38 commercial receiving theatres. These excluded institutions are not researched as study subjects. Affiliate theatres are outside the primary frame. This is an explicitly defined industry-membership population, not a claim that every geographical or journalistic definition of the West End yields 38. The Arts Theatre is shown as closed in Official London Theatre's separate directory; its Marble Arch replacement appears among SOLT affiliates and is therefore outside this frame. Preserve this boundary rather than silently counting the old and replacement sites together.
Reconcile the original 33 distinct venues in five corporate operating portfolios with the five other included venues. Normalize Duke of York's/Tom Stoppard, Playhouse/Kit Kat Club, Sondheim/Queen's, and Trafalgar names. SOLT's old name or outbound ticketing link does not override an operator's current history. Adelphi is a joint LW/Nederlander row and is counted once. Main statistic: 33/38 venues in the five groups' operating portfolios, including their one joint venue. This is not 33 proven freehold titles.
Property relationships remain source-specific. Delfont Mackintosh explicitly states six freeholds and two long leases. Criterion's history establishes the operating trust's lease. DLT states full ownership of Shaftesbury. Haymarket reports its acquisition by Access Entertainment. St Martin's own history names the Willoughby de Broke family, but this study does not establish all legal interests. No registry research or inference from ticket-selling websites.
Capacities are source-reported figures, not certified occupancy or same-night sellable inventory. Preserve maximum, technical, hire and temporary configurations. Shaftesbury's dated refurbishment notice takes precedence over older general figures: 1,015 during the 2026–27 works, 1,300 usual capacity expected afterward. Criterion says 590 for venue hire. Haymarket says up to 860. St Martin's gives a component breakdown totalling 552. These source conflicts are recorded; a single historical number should not be described as a permanent physical fact.
Public St Martin's page text is client-rendered. Its site-served page component contains both the 552-seat breakdown and ownership paragraph; the component URL and hash are preserved alongside the human-facing source URL. Existing 33-venue source and capacity-note tables remain in the package. Operator counts are the principal complete-population result; seat totals sum heterogeneous reported configurations and need that qualification.
Version 3.0 records published ownership descriptions separately from operating portfolios. DMT expressly uses ownership to include its two long leases, so an owned-theatre description need not mean freehold land. DMT's eight, Nimax's six, LW's six (including the joint Adelphi) and ten ATG venues described in industry reporting form 30 distinct source-supported ownership rows. Nederlander's exclusive two are outside this conservative lower bound pending more explicit venue-specific ownership evidence; this does not classify them as non-owned. @sohoplace remains Nica Burns-owned/Nimax-operated, not inferred to be group-owned. No registry or land-title research is claimed.