Every profile Archive Partners tracks carries a Companies House SIC code — the five-digit classification a business declares at incorporation and reaffirms with every annual filing. Looked at one company at a time, a SIC code is a bureaucratic footnote. Looked at across the roughly 650 companies in our tracked cohort, the distribution of those codes is a rough sketch of what the UK’s mid-market economy is actually made of right now.
Construction and property are the single biggest cluster. Four codes tell that story: 41100 (development of building projects, 18 companies), 41201 and 41202 (construction of domestic and commercial buildings, 18 and 22 companies respectively), and 43999 (other specialised construction activities, 19 companies). Add them together and building-related activity accounts for over 75 appearances across the cohort — comfortably the largest single theme in the data. That’s consistent with what anyone watching UK GDP components would expect: construction has stayed a disproportionately large employer and turnover generator relative to its share of headline economic commentary, and our filings data reflects that at the company level rather than the sector-index level.
The second-largest cluster is less visible and more interesting: holding company structures. SIC 64209 (“activities of other holding companies n.e.c.”) appears against 28 companies, and 82990 (“other business support service activities n.e.c.”) — often used as a catch-all by group-structure subsidiaries and management-services vehicles — tops the entire list at 30 appearances. Together that’s 58 filings that aren’t describing an operating business at all, but a layer of corporate structure sitting above or alongside one. For anyone doing vendor risk or M&A sourcing work, that’s a useful reminder: a SIC code search for “who does X” will systematically undercount, because a meaningful share of the corporate entities in any given group don’t file under the SIC code of what the group actually does — they file under “holding company” or “business support,” and the operating entity is a different registered number entirely. This is exactly the kind of structural blind spot that raw Companies House search misses and that cross-referencing officer records and registered addresses (which Archive Partners does for every tracked company) is built to catch.
Technology is the third cluster, and a smaller one than the sector’s public profile might suggest. IT and software-related codes — 62090 (other IT service activities), 62012 (business and domestic software development) and 62020 (IT consultancy) — together account for 34 appearances, roughly half the construction total. That’s not a comment on the health of UK tech; it reflects that our cohort skews toward the turnover-heavy, often less digitally visible mid-market firms that are Archive Partners’ core coverage area, rather than the venture-backed software companies that dominate tech-sector headlines. It’s a useful check on assumption, though: if you’re building a supplier panel or a watchlist and expect “most companies now have a software layer,” the filings say the base rate of primary tech classification is lower than that intuition, even before accounting for the holding-company undercount above.
Further down the list, freight transport by road (SIC 49410, 11 companies) and “other professional, scientific and technical activities” (74909, 9 companies) round out a top ten that reads as a fairly conventional cross-section of British SME activity — property, logistics, professional services, with technology present but not dominant.
None of this is a dramatic finding on its own. The value is cumulative: tracked over successive weeks, shifts in this distribution — a sudden concentration in one construction sub-code, a new cluster of holding-company registrations tied to a particular postcode or officer, a quiet rise in a previously minor SIC — are the kind of early signal that’s invisible in any single company’s accounts but visible the moment you can see the whole cohort at once. That’s the premise this routine exists to test: that reading iXBRL filings in aggregate, every week, surfaces structural patterns that reading them one company at a time never will.