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CFTC · US Digital Assets substrate v1

Staff Letter 25-40 became 26-05.
The models didn't notice.

The CFTC's December 2025 digital asset collateral package was reissued in February 2026 under a new letter number. Frontier AI models conflated the two letters, missed the reissuance entirely, and compounded that with misreadings of the OCC interpretive letter and the haircut worst-case selection rule.

📅 Published 7 Jun 2026 ⚙️ Methodology v2.3 🔗 Staff Letters 25-40 · 26-05
Staff Letter 25-40
December 2025 — original issuance
Staff Letter 26-05
February 2026 — reissuance
Model output
Conflated · treated as one
📰Read the public briefing for this regulation
The regulatory package

Three instruments, one framework — and one reissuance the models missed

The CFTC's December 2025 digital asset collateral package sits across three instruments. Staff Letter 25-40 set out the initial no-action position on bitcoin, ether, and certain stablecoins as acceptable collateral for futures commission merchants and derivatives clearing organisations. The accompanying tokenized asset staff guidance addressed how tokenized versions of traditional assets fit within the existing collateral framework. Then, in February 2026, Staff Letter 25-40 was reissued as Staff Letter 26-05, carrying technical clarifications on the haircut selection methodology.

Both models, web search on, treated 25-40 and 26-05 as two names for the same document. Their outputs treated 25-40 and 26-05 as alternative references to the same document, collapsing a two-step issuance sequence into a single event and, in doing so, rendering the February 2026 clarifications invisible.

Bitcoin
Covered · 25-40 / 26-05
Ξ
Ether
Covered · 25-40 / 26-05
Certain Stablecoins
Covered — scope conditions apply
Finding: OCC Interpretive Letter 1183

The models couldn't name the right OCC instrument

The CFTC staff letters sit alongside OCC Interpretive Letter 1183, which addresses how national banks may hold cryptocurrency assets. When asked about the OCC instrument that contextualises the CFTC collateral guidance, both models either named a wrong letter number or produced a plausible-sounding OCC reference that does not exist in the OCC's published record.

Hallucination Type: Instrument Identification Fabrication

Models produced OCC interpretive letter references that are either wrong or non-existent when asked to identify the OCC instrument contextualising the CFTC digital asset collateral guidance. OCC Interpretive Letter 1183 is the correct instrument.

// Correct instrument record
cftc_staff_letter_dec_2025: "Staff Letter 25-40"
cftc_reissuance_feb_2026: "Staff Letter 26-05"
occ_contextual_instrument: "Interpretive Letter 1183"
assets_covered: ["bitcoin", "ether", "certain_stablecoins"]
// Model output (both Opus 4.7 + Sonnet 4.6)
cftc_letter_status: "25-40 and 26-05 treated as same document" // ✗
occ_instrument: "Wrong or fabricated letter number" // ✗
Finding: Haircut worst-case selection rule

The haircut methodology — and where the models went wrong

Staff Letter 26-05 includes a clarification on how haircuts for digital asset collateral should be selected where multiple scenarios are applicable: the worst-case haircut governs. This is a specific and consequential rule, the wrong haircut selection means under-collateralisation against the regulator's required buffer. Both models, when asked to describe the haircut selection methodology, produced outputs that either omitted the worst-case selection requirement entirely or softened it to a best-estimate basis.

HAIRCUT SELECTION — REGULATORY RULE vs MODEL OUTPUT Scenario A 12% Scenario B 18% Scenario C 9% CFTC Rule: Worst-case governs Apply 18% Model output: Omitted / softened Best-estimate basis ✗ Both models omitted or softened the worst-case selection requirement in Staff Letter 26-05
Regulatory rule (Staff Letter 26-05): when multiple haircut scenarios apply, the worst-case governs. Both models produced outputs that omitted or softened this requirement.
Model output (both models)
Haircut selection described as a best-estimate or average-basis calculation, or the worst-case requirement omitted entirely.
Staff Letter 26-05 (actual rule)
Where multiple haircut scenarios apply, the worst-case haircut governs. Not an average. Not a best-estimate. The most conservative applicable figure.
Operational signal for AI labs

Where the failure surface sits in production

The failure modes here, reissuance conflation, wrong instrument identification, and worst-case rule omission, surface when a model is used in FCM compliance workflows, risk function collateral management, or fintech product embedding. An FCM compliance officer who asks a frontier model about the current CFTC digital asset collateral position and receives output that misses the 26-05 reissuance is operating from an outdated regulatory picture. A product team embedding CFTC collateral logic that receives the wrong haircut selection rule is under-collateralising against the regulator's required buffer.

The tokenized asset staff guidance adds a further complexity layer: models asked about tokenized versions of traditional assets within the CFTC framework need to distinguish the tokenized-asset guidance from the digital-asset collateral guidance. The audit found this boundary to be another failure surface, with models conflating coverage conditions between the two instruments.

RLB-H-US-CFTC-DIGITAL-ASSET-25-40-26-05 OCC Interpretive Letter 1183 Worst-case haircut selection

Full regulation hub: DIGITAL-ASSET-COLLATERAL-TOKENIZED-ASSETS-STAFF-GUIDANCE-2025 →

Hallucination Register: reglegbrief.com/hallucination-register/