Definitions for the regulatory, technical, and operational vocabulary used in stablecoin reserve compliance. Accurate as of 2026. Categories: regulatory framework, blockchain architecture, attestation standards, and TCB-specific terminology.
The American Institute of CPAs attestation standard governing examination engagements. The governing framework for stablecoin reserve attestation under the GENIUS Act. Every TCB deliverable is formatted to the procedures contemplated by this standard.
AT-C Section 205 requires the CPA to evaluate whether a subject matter — in this case, the issuer's reserve assertion — conforms to suitable criteria. The CPA issues a written conclusion. For reserve attestation, the subject matter is: reserve assets equal or exceed coins in circulation.
A CPA's written conclusion that a subject matter conforms to suitable criteria based on documented evidence examined. Distinct from an audit, which involves forming an opinion on the fairness of financial statements. Reserve attestation under the GENIUS Act requires a CPA to attest that reserves equal or exceed circulation. Not to audit the issuer's financial statements.
TCB produces the reconciliation package. The CPA produces the attestation. These are separate functions and separate documents. TCB is not in the attestation chain.
A comprehensive examination of financial statements by an independent CPA resulting in an opinion on whether those statements present fairly, in all material respects, the financial position and results of operations. An audit is not what the GENIUS Act requires for reserve compliance.
The GENIUS Act requires monthly CPA-attested reserve proof under an examination engagement framework. A more targeted engagement than a full financial audit. Conflating the two is a common misunderstanding in early issuer conversations.
An ERC-20 Transfer event where the destination address (to) is the zero address (0x0000000000000000000000000000000000000000). Represents the destruction of tokens, reducing circulating supply. Burn events decrease the On-Chain Supply Change figure.
In Phase I data collection, burn events are queried directly from on-chain event logs using Dune Analytics. The zero-address burn pattern is consistent across all EVM chains in scope.
The formal name for TCB's core workflow. Used in all legal documents, SOPs, engagement letters, and CPA communications. Describes the process of collecting on-chain supply data, reconciling it against reserve confirmation, and delivering a structured package on a monthly cadence.
The total on-chain token supply at the end of a reporting period. Calculated as: Opening On-Chain Supply + Total Mints - Total Burns. The figure that reserve assets must equal or exceed for the issuer to achieve PASS status.
Closing On-Chain Supply is an auto-calculated field in both the L1 and L2 templates. It is never entered manually. It flows directly into the Reserve Position section.
PASS if Fiat Reserve Balance is greater than or equal to Closing On-Chain Supply. FAIL if reserve assets fall short of circulation. Auto-calculated in Section 3 of both the L1 and L2 templates.
The period convention [period_start, period_end): inclusive of the start date, exclusive of the end date. A transaction occurring exactly at midnight on the first day of a period is included; a transaction at midnight on the first day of the next period is excluded.
This prevents double-counting across adjacent reporting periods and is the method documented in Part E: CPA Verification Parameters. Consistent application is necessary for the CPA's examination to be reproducible.
The conversion of raw on-chain token values to human-readable dollar amounts. USDC uses 6 decimal places. Raw token values from on-chain event logs must be divided by 106 to produce USD figures. A raw value of 2500000000000 represents $2,500,000.
Decimal precision varies by token. The correct decimal count is confirmed per issuer at engagement initiation and documented in Part E.
The Ethereum token standard governing fungible tokens. Defines the Transfer event that TCB queries for mint and burn detection. All ERC-20 tokens emit a Transfer event on every token movement, with from, to, and value fields. Mint events have from = zero address. Burn events have to = zero address.
The execution environment shared by Ethereum and compatible chains (Polygon, Arbitrum, Base). EVM chains implement the same smart contract bytecode, the same Transfer event structure, and the same zero-address mint/burn pattern. This is why Phase I data collection uses a single query methodology across all four chains.
Non-EVM chains (Solana, Tron) do not share this event model and require chain-specific collection architecture. This is why they are Phase II.
The Guiding and Establishing National Innovation for US Stablecoins Act. Passed the US Senate 66-32 in May 2025. Establishes the federal compliance framework for permitted payment stablecoin issuers, creates mandatory reserve attestation requirements, and defines the licensing tracks for issuers (OCC-chartered, state-regulated, and NCUA for credit union subsidiaries).
The GENIUS Act requires every permitted payment stablecoin issuer to produce monthly CPA-attested proof that reserve assets equal or exceed coins in circulation. This is a condition of legal operation, not a voluntary disclosure. The compliance date is the earlier of January 18, 2027 or 120 days after final regulations are published.
The issuer-facing summary document in the TCB attestation package. Contains the reporting period, On-Chain Supply Change (Sections 1-2), scope disclosure (Section 2B), reserve position (Section 3), and CPA attestation reference (Section 4). Formatted for executive review. Totals and conclusions, not chain-level detail.
Goes to issuer leadership and the attesting CPA. Delivered at every tier, every engagement.
The full working document the CPA uses to perform the examination. Contains everything in L1 plus: chain-by-chain On-Chain Supply Change (Section B.1), scope reconciliation against issuer-published all-chain figures (Section B.2), and a Part E tab. Every variance is classified. Every figure is traceable.
Available to the issuer directly at Standard tier and above. Delivered to the CPA at every tier.
An ERC-20 Transfer event where the source address (from) is the zero address (0x0000000000000000000000000000000000000000). Represents the creation of new tokens, increasing circulating supply.
In Phase I data collection, mint events are queried from on-chain event logs. The zero-address mint pattern is consistent across all EVM chains.
Blockchain architectures that do not use the Ethereum Virtual Machine. Solana (Sealevel runtime) and Tron (TRC-20) are the primary non-EVM chains carrying significant USDC supply. These chains do not use the ERC-20 Transfer event model, so mint and burn events cannot be detected using the same query methodology as Phase I.
Solana and Tron are Phase II. Their net supply movements during a reporting period are the primary source of scope variance between TCB's Phase I figures and the issuer's published all-chain circulation.
Net change in token supply during a reporting period. Calculated as Total Mints minus Total Burns. Never referred to as "net mints" or "gross supply change." A positive figure indicates net issuance. A negative figure indicates net contraction.
The total on-chain token supply at the start of a reporting period. For all periods after the first, this should equal the prior period's Closing On-Chain Supply. Any discrepancy should be investigated and disclosed before the package is delivered. An issuer-entered field in both the L1 and L2 templates.
A permanent reference document included in every L2 package, at every tier, every cycle. Defines the attestation standard, engagement type, data sources, mint and burn event definitions, decimal normalization method, date boundary protocol, chain scope, and compliance threshold.
Part E is what makes the CPA's attestation defensible. Every figure in the package can be traced back to a documented, reproducible procedure. It is non-depth-gated by design.
A stablecoin that meets the requirements for legal operation as a payment instrument under the GENIUS Act. Requires a federal or state license, reserve requirements, and mandatory monthly CPA attestation. Under the March 2026 SEC/CFTC joint interpretive guidance, payment stablecoins are classified as a distinct category in the five-category digital asset taxonomy, separate from digital commodities and securities.
The initial TCB engagement scope covering four EVM-compatible chains: Ethereum, Polygon, Arbitrum, and Base. Phase I is operational and available from engagement initiation. These four chains cover the majority of USDC circulation and share a common data collection methodology.
TCB's planned future engagement scope covering non-EVM chains: primarily Solana and Tron, plus Avalanche, Optimism, Noble (Cosmos), Stellar, Hedera, Algorand, Sui, and Aptos. Phase II chains require chain-specific data collection architecture that differs from Phase I's EVM event log query approach.
During Phase I engagements, Phase II chain supply movements are the primary explanation for scope variance between TCB's reported figures and an issuer's published all-chain circulation. That variance is expected, classifiable, and disclosed in every L2 package.
The issuer-signed document confirming Fiat Reserve Balance for a given reporting period. One document per period. The issuer's designated finance contact signs this document. TCB uses the confirmed figure as the fiat reserve input to the reconciliation. TCB does not have access to bank accounts or custody systems. The reserve confirmation is the sole fiat data source.
Fiat Reserve Balance divided by Closing On-Chain Supply. Must be greater than or equal to 100% for PASS status. A Reserve Ratio above 100% indicates a surplus. Below 100% indicates a deficit and a compliance event. Auto-calculated in Section 3 of both templates. Formatted to two decimal places (e.g., 100.17%).
The difference between TCB's Phase I on-chain supply figure and the issuer's published all-chain supply figure. Expected in every Phase I engagement. Disclosed in Section B.2 of the L2 Reconciliation Exhibit. Always described as expected, classifiable, and disclosed. Never described as a reconciliation error.
The January 2024 USDC proof-of-process validation produced a $340M scope variance, attributable to Solana and Tron supply movements during the period. The Phase I reconciliation was accurate within its defined scope.
A cryptocurrency designed to maintain a stable value, typically pegged 1:1 to the US dollar. Under the March 2026 SEC/CFTC joint interpretive guidance, payment stablecoins are a distinct category in the five-category digital asset taxonomy, separate from digital commodities and digital securities. USD-denominated payment stablecoins issued by US entities are subject to GENIUS Act requirements.
Fiat Reserve Balance minus Closing On-Chain Supply. A positive figure (surplus) indicates reserves exceed circulation: PASS. A negative figure (deficit) indicates reserves fall short: FAIL. Auto-calculated in Section 3 of both templates. Negative values display in parentheses per financial convention.
A running on-chain supply record maintained across all reporting periods. Available to Premium tier clients. Updated each monthly cycle with closing supply figures, cumulative mint and burn totals, and chain-level breakdowns. Gives the issuer and CPA a continuous historical record rather than isolated monthly snapshots. Formally referenced as the MultiChain Weekly Tracker in internal TCB documentation.
The Ethereum address 0x0000000000000000000000000000000000000000. In ERC-20 token contracts, the zero address serves as the origin of mint transactions (tokens are created "from" the zero address) and the destination of burn transactions (tokens are destroyed "to" the zero address).
Filtering Transfer events by zero-address from or to is the basis of Phase I on-chain supply change detection. This method is deterministic and reproducible from public on-chain data.