11 · The Aktiengesellschaft that does not appear in the taxonomy

The drift in the previous chapter concerned the declaration format. The second carrier, the XBRL taxonomy, has a gap of its own; it reaches further than its size suggests.

On slide 6 of its information event of 25.08.2025, the Zürcher Finanzdirektion draws an arrow: Buchhaltungssystem → Export → E-Bilanz (XBRL, CH-Taxonomie) → Import (XBRL) → ZHcorporateTax. The slide is headed «E-Bilanz ab Steuerperiode 2025» (E-Bilanz from tax period 2025). Two slides earlier, slide 4 gives the population this is meant to apply to: «Insgesamt gab es 2024 rund 97'000 JP» (in 2024 there were around 97'000 legal entities in all), split into «AG 46% · GmbH 48% · Genossenschaften 1% · Vereine, Stiftungen & übrige JP 5%». Worked through, that gives some 44'600 Aktiengesellschaften and some 46'600 GmbH.

The taxonomy that the same slide deck draws as the carrier of that import knows nine legal forms. The plain Aktiengesellschaft is not one of them.

The finding in the artefact

In ch-taxonomy-def-2024-06-23.xml, the definition linkbase of the delivered CH-Taxonomie, exactly nine domain-member arcs hang from ct:LegalFormDomain. They are listed here in the order of their order attributes, with the German standard labels from ch-taxonomy-lab-de-2024-06-23.xml:

There is no PublicLimitedCompanyMember. The string does not occur in the schema file; the only match for PublicLimited* is the fifth member, the AG & Co. KG. The Kommandit-Aktiengesellschaft can be represented, and so can the Aktiengesellschaft & Co. Kommanditgesellschaft; the Aktiengesellschaft itself has no value of its own.

This is not a consultation artefact. The same finding sits in ch-taxonomy-2025-05-31.xsd from the swissdec Transmitter package of the 06.03.2026 release: 519 element declarations, 71 of them *Member, the same nine legal-form members, and no PublicLimitedCompanyMember. Two vintages, two delivery routes, the same inventory.

Put plainly, and without a judgement about any person or organization: the taxonomy that slide 6 draws as the import carrier cannot express the legal form of 46 % of the canton's legal entities as a value of its own. A second finding sits on the same slide and appears in no discussion: in Zürich the GmbH is the more frequent legal form.

The bridge that does exist — and that we ourselves denied

Our own crawl manifest MANIFEST-crawl-c-standards.md closes §5 with the sentence: «The two standards do not reference each other, at all.» We withdraw that sentence here. It is wrong, and the measurement that refutes it sits in the same file as the nine legal forms.

The reference linkbase ch-taxonomy-ref-2024-06-23.xml has carried 425 referenceArcs since 23.06.2024. Of these, 132 carry the entry <ref:Name>Tax code</ref:Name> with <ref:Paragraph> values that are exactly eCH-0276 position IDs — A1000, A1109, B2700, C3000, and so on. Verbatim:

<link:reference xlink:label="lbl14573" id="id7584">
  <ref:Name>Tax code</ref:Name>
  <ref:Paragraph>B2700</ref:Paragraph>
</link:reference>

131 distinct codes across 132 concepts. Of those, 130 appear as positions in the SSK-Regelwerk; B2720 appears in no eCH-0276 artefact and is a dangling reference. The manifest counted the prose of the two twenty-page main documents, where the zero count holds, and drew from that a conclusion about the standards as a whole. The connection sits in the annexes.

Two refinements make the finding sharp rather than large. First: the Tax code entries are the only ones without a <ref:Publisher>. The other three families name theirs — Schweizer Kontenrahmen KMU with publisher veb.ch, kvschweiz (176 arcs), Swiss Taxonomy Code with publisher xbrl.ch (84), and the Obligationenrecht (32). Second: the coverage ends exactly where the tax computation begins. It spans dialogues A 31 of 34, B 39 of 46, C 60 of 86 — assets, liabilities, and the income statement. From dialogue D, the tax adjustments, nothing. The bridge exists, it is anonymous, and it stops before matters turn fiscal.

What the taxonomy hangs on

176 references to the Schweizer Kontenrahmen KMU, 32 to the Obligationenrecht. What this debate calls «die OR-Taxonomie» (the OR taxonomy) is bound first to a chart of accounts, second to the law, and third, namelessly, to eCH-0276.

That also explains the granularity that appears in neither of the two standards and that the canton states on request — questions and answers from the Steueramt, 08.09.2025:

«Die XBRL-Instanzdokumente für Steuerangelegenheiten liefern mehrheitlich Daten auf der Ebene von Kontogruppen. Abweichend hiervon enthalten sie dort Kontosaldi, wo es das automatische Ausfüllen der Steuererklärung erleichtert (z.B. im Bereich des Anlagevermögens und der dazugehörigen Abschreibungen).» (the XBRL instance documents for tax matters deliver data mostly at the level of account groups; departing from that, they carry account balances where this eases the automatic completion of the tax return, e.g. for fixed assets and the associated depreciation)

A cross-check against the artefact. The 2018 manual that the canton of Obwalden published on 16.02.2023 as its E-Bilanz guidance gives an example account: «So wird z.B. eine Kontonummer 1020 in der Klassierung der OR-Taxonomie dem Bankguthaben zugeordnet.» (thus an account number 1020, for example, is assigned to bank balances in the classification of the OR taxonomy). The reference linkbase carries no anchor 1020. The nearest is the group 100 → ct:CashAndCashEquivalents. Of the 176 chart-of-accounts anchors, 57 are three-digit and 85 four-digit. The machine-readable Jahresrechnung is not the general ledger.

What gets checked

All three figures counted from primary sources on 04.08.2026:

• 4 formula assertions in the complete formula linkbase ch-taxonomy-for-2024-06-23.xml. The four test expressions, verbatim: $Assets eq $EquityAndLiabilities · $ProfitOrLossCarriedForwardPeriodEnd eq $ProfitOrLossCarriedForwardPeriodStart + $IncreaseDecreaseOfProfitOrLossCarriedForward · $FiscallyRecognisedCapitalReservesEnd eq $FiscallyRecognisedCapitalReservesStart - $DistributionOfReservesFromCapitalContributions · $CashAndCashEquivalentsEnd eq $CashAndCashEquivalentsStart + $IncreaseDecreaseInCashAndCashEquivalents.
• 211 calculationArcs, 21 of them with weight="-1".
• Set against that, 1'432 rule lines in the SSK-Regelwerk (sheet Regeln eCH-0276, as at 31.03.2026), 670 of them with the error class Fehler / Erreur.

No figure for ERiC stands here, deliberately. It becomes citable only once it has been counted from our own rule catalogue, and in this session it has not been.

A measured defect that is growing

German standard labels that sit on more than one concept: 5 in the 2024-06-23 version, 7 in v0.9.2. Five of the seven pair a monetary concept with its text-block twin and resolve through the type. Two do not:

• «Gesetzliche Kapitalreserve» on ct:OtherCapitalReserves and ct:StatutoryCapitalReserve — both monetaryItemType, both credit, both instant.
• «Jahresgewinn (Jahresverlust)» on ct:AnnualProfitOrAnnualLoss (credit/instant) and ct:ProfitOrLoss (credit/duration), separable only by the periodType.

The second case is the one that eCH-0276 split, in its patch version, into a balance-sheet side and an income-statement side. Each standard arrived independently at the finding that the annual result needs two carriers, and neither says so in prose.

The state of the artefact, set out plainly

The documentation carries the version v0.9.2 and, on every page, the header «Guidance and consultation»; feedback by e-mail, with no stated deadline. The SSK-Regelwerk declares the same taxonomy binding: «Falls die E Bilanz nicht elektronisch übermittelt wird, ist die Jahresrechnung in der Deklarationslösung manuell zu erfassen. Auch für die manuelle Erfassung gilt die CH Taxonomie 2025.» (if the E-Bilanz is not transmitted electronically, the Jahresrechnung is to be entered manually in the Deklarationslösung; the CH Taxonomie 2025 applies to manual entry as well)

The five 2025-05-31 entry points returned HTTP 404 in our crawl on 04.08.2026. The schemas sit only in the swissdec ZIP, and there without a single linkbase: the directory schema/ contains zero .xml files. A vocabulary, then, without rules, without the four assertions, and without the 131 Tax code references. Addendum of 06.08.2026: On enquiry, Verein XBRL Schweiz named the route — «Bezugsort: Die CH-Taxonomie 2025 beziehen Sie über das XBRL Taxonomy Registry. Den Link dazu finden Sie auf unserer Website unter ‹Taxonomie Schweiz (OR)› (ch.xbrl.org); im Registry wählen Sie Switzerland aus. CH Taxonomy 0.9.2» (the CH-Taxonomie 2025 is obtained through the XBRL Taxonomy Registry; the link is on their website under ‹Taxonomie Schweiz (OR)›, and in the Registry one selects Switzerland) — and the split that accounts for the finding above: «Umfang: Über das Registry erhalten Sie das vollständige Taxonomiepaket inklusive Label-, Präsentations-, Berechnungs- und Definitions-Linkbases. Das swissdec-Transmitter-Paket enthält nur die Schemadateien.» (the Registry supplies the complete taxonomy package including label, presentation, calculation and definition linkbases; the swissdec Transmitter package contains only the schema files). On the entity identifier: «Ja, die UID mit scheme="https://www.uid.admin.ch" ist auch für die CH-Taxonomie der vorgesehene Weg.» (yes, the UID with that scheme is the route foreseen for the CH-Taxonomie as well). (Verein XBRL CH, written information of 06.08.2026.) That does not explain the 404 — the entry points remained unreachable — but it names where the missing linkbases live. Our own holdings carry the same split: the 2024-06-23 package is complete, with label, presentation, calculation and definition linkbases; for 2025 we hold only the two schemas from the swissdec package and not one linkbase. Three counts for the same year stand side by side: 453 concepts (2024-06-23, as delivered), 519 (ch-taxonomy-2025-05-31.xsd in the swissdec package), and 465 (published concept list v0.9.2).

That leaves the clause that accounts for the 5 %. Every unmapped C-dialogue position is a Verein or Stiftung line — C3950 Mitgliederbeiträge, C3951 Erträge aus Spenden, Schenkungen und Vermächtnisse, C3952 Gönnerbeiträge, all three in the Regelwerk with the condition «Gesellschaftsform = Verein» (company form = Verein). That is exactly the «Vereine, Stiftungen & übrige JP 5%» from slide 4.

Two documents, one slide deck, one taxonomy. Everything above is a statement about files, not about the conduct of a person, and it can be checked in four minutes: open the definition linkbase, count the nine arcs on ct:LegalFormDomain, search for PublicLimitedCompanyMember, and put slide 4 beside it.

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