identifier,issuer,format,scope,reuse_rule,primary_in,also_appears_in,notes
RSSD ID,Federal Reserve Board (National Information Center / RSSD database),"Sequential integer with check digit, no fixed length","Every entity the Fed tracks (banks, BHCs/FHCs, branches, savings institutions, holding-company tiers, some foreign and non-bank entities)","Never changes, never reused; one per entity for its entire life cycle; persists after liquidation or closure","NIC/NPW, FFIEC Call Report, FR Y-9C and the FR Y-series","FDIC datasets (FED_RSSD), FFIEC CDR, FRED bank series, academic bank panels, HMDA pre-2018 (agency code 2)",Most stable join key across charter changes and over time; carries no inherent attribute info (ID_RSSD in NIC)
FDIC Certificate number,Federal Deposit Insurance Corporation,Sequential integer (no check digits),Every FDIC-insured depository institution (banks and savings institutions),"Unique per insured institution; assigned at insurance, retained through life; not recycled in practice",FDIC BankFind / SDI / Summary of Deposits / failures lists,"NIC (ID_FDIC_CERT attribute), HMDA pre-2018 (agency code 3)",Sequential-integer system - not globally unique without an agency qualifier; assigned per head-office depository
OCC Charter number,Office of the Comptroller of the Currency,Sequential integer,National banks and (since 2011-07-21) federal savings associations / federal thrifts,Assigned at chartering and retained through life,OCC chartering data,"NIC (ID_OCC attribute), HMDA pre-2018 (agency code 1)",Since 2011-07-21 the OCC Charter field also stores national thrifts as thrift docket + 700000
NCUA Charter / ID number,National Credit Union Administration,"Sequential integer; banded 1-59999 Federal, 60000-79999 Federally Insured State Chartered, 80000+ Non-Federally Insured",Federally insured credit unions (and some non-federally-insured),Assigned at chartering and retained through life,NCUA Call Report / Research-a-Credit-Union,"NIC (ID_NCUA attribute), HMDA pre-2018 (agency code 5)",Sequential-integer system - not globally unique without an agency qualifier
LEI,GLEIF governs; issued by accredited Local Operating Units (LOUs) overseen by the LEI ROC,"20-char alphanumeric: chars 1-4 LOU prefix, 5-18 entity-unique, 19-20 MOD-97-10 checksum (ISO/IEC 7064)",Any legal entity participating in financial transactions worldwide,Permanently unique to one entity; never reused; must be renewed annually to stay active but the code persists,HMDA (filer id) 2018-forward,"SEC/CFTC swap reporting, FR Y-series LEI fields, GLEIF golden-copy file, NIC (ID_LEI attribute)",ISO 17442; exists only from ~2012 forward - cannot back-fill pre-2012 panels (coverage gap)
ABA Routing Transit Number,American Bankers Association via its registrar (currently LexisNexis Risk Solutions; historically Accuity),9 digits FFFF AAAA C: Fed routing symbol (4) + ABA institution id (4) + MOD-10 check digit (1),Financial institutions eligible for a Federal Reserve master account (payment routing),Tied to payment routing not entity identity; reassignable/retirable after mergers; reusable across non-concurrent entities; one institution may hold many,Fedwire/ACH routing files / FedACH / E-Payments Routing Directory,NIC (ID_ABA_PRIM attribute),Not an entity key - never use as a persistent entity identifier
OTS Docket number / Thrift ID,(former) Office of Thrift Supervision - defunct since 2011-07-21,Numeric docket; NIC field 9 chars but only right-most 5 used,Savings institutions / thrifts (legacy),Legacy identifier; OTS functions transferred to OCC/FDIC/Fed under Dodd-Frank,Legacy thrift datasets / historical TFR (Thrift Financial Report) data,"NIC (ID_THRIFT, ID_THRIFT_HC attributes), HMDA pre-2018 (agency code 4, legacy)",New thrift supervision uses OCC Charter / RSSD
Federal Tax ID / EIN,Internal Revenue Service,9 digits NN-NNNNNNN,Any US entity with tax obligations,Permanently assigned to a legal entity; not recycled to another entity,(not a primary bank-regulatory key),"SEC filings, HMDA pre-2018 fallback respondent id, NIC (ID_TAX attribute, eff. 2008-12-31)",Multiple entities under one parent each have their own EIN
CIK,SEC EDGAR,"Integer, zero-padded to 10 digits in API paths","Any EDGAR filer (companies including public BHCs, funds, individuals)",Assigned at filer signup; unique to the filer and not recycled,SEC EDGAR submissions / XBRL APIs and all SEC filings,(no official CIK-RSSD crosswalk published - UNVERIFIED),Independent of RSSD/CERT; joining public-BHC financials to regulatory data needs an external crosswalk
CUSIP,CUSIP Global Services (operated for the American Bankers Association),9 chars: 6-char issuer + 2-char issue + 1 check digit,Securities (equity/debt) of issuers including public BHCs,Identifies a security not the legal entity; reassignment governed by CGS rules,securities datasets,"SEC EDGAR full-text search (searchable field), NIC (ID_CUSIP attribute)",Ticker symbols (issued by listing exchange NYSE/Nasdaq) can change/be reused across issuers - also not a stable entity key