canonical: https://jentic.com/apis/cusip.com/cusip # CUSIP Data API Jentic maintains a curated, agent-optimized OpenAPI specification for CUSIP Data API, kept validated and agent-ready. CUSIP Global Services also publishes its own OpenAPI document covering the same operations, linked in the FAQ below. CUSIP Data API exposes CUSIP Global Services' identifier database, the canonical reference for the nine-character CUSIP codes that uniquely identify financial securities for clearing and settlement. Endpoints cover CUSIP and ISIN lookup, syndicated loan and option/future identifiers, ticker symbol resolution, associated issuer and corporate-action search, and carbon credit (VCM) identifiers. Authentication is by an X-API-KEY header. ## For AI agents Resolve CUSIP and ISIN identifiers, look up issuer and security metadata, map tickers to CUSIPs, and search syndicated loan, option, and carbon credit instruments. ## Scope Does not handle trading, settlement instructions, or pricing - use for CUSIP and ISIN identifier lookup and security reference data only. ## Capabilities - Resolve a CUSIP or ISIN to security metadata including issuer, issue type, and identifier history - Map a ticker symbol on a specific exchange to the corresponding CUSIP and ISIN - Search syndicated loan CUSIPs by deal, agent, and borrower attributes - Look up option and future CUSIPs by underlying or comma-delimited identifier list - Search corporate-action records and associated issuer relationships across the CUSIP database - Retrieve carbon credit (VCM) CUSIPs by identifier or filter search ## Use cases ### Security Master Enrichment Enrich an internal security master file by resolving CUSIPs and ISINs to canonical issuer, issue type, and identifier metadata from CGS. Treasury, fund administration, and middle-office teams use the CUSIP Data API to keep reference data accurate without manual data-vendor reconciliation. The API supports both single-identifier and comma-delimited list lookup for batch enrichment. Example prompt: Call GET `/cusip/{cusipList}` with a comma-delimited list of 50 CUSIPs from the security master and persist the returned issuer and issue-type fields ### Ticker to CUSIP Mapping Map exchange ticker symbols to CUSIPs for trade matching, regulatory filings, and downstream systems that key on CGS identifiers. Use `/cusipTickerSymbol/ticker/{tickerSymbol}` to resolve a ticker, or `/cusipTickerSymbol/cusip/{cusip}` for the reverse direction. Example prompt: Call GET `/cusipTickerSymbol/ticker/AAPL` to resolve the Apple Inc ticker to its CUSIP and ISIN for a trade ticket ### Syndicated Loan Identifier Search Search and resolve syndicated loan CUSIPs for loan trading, agent reporting, and portfolio reconciliation. The `/cusip/loan/search` and `/cusip/loan/{cusip}` endpoints expose CGS's loan identifier coverage with filters for borrower, agent, and deal attributes. Example prompt: Call GET `/cusip/loan/search` with a borrower filter to retrieve all loan CUSIPs for that borrower for a portfolio review ### Corporate Action and Issuer Research Research issuer relationships and corporate-action history across the CUSIP database. Use `/cusip/associatedIssuer/search` to find related issuers under a parent and `/cusip/corporateAction/search` to surface action records (mergers, splits, name changes) for a CUSIP or issuer. Example prompt: Call GET `/cusip/corporateAction/search` with the issuerNumber filter to surface all corporate actions affecting a parent issuer's outstanding securities ### AI Agent Identifier Resolution via Jentic An AI agent helping a research analyst convert a list of tickers, ISINs, and CUSIPs into a single identifier scheme uses Jentic to drive the CUSIP Data API. The agent searches for 'lookup cusip', loads the appropriate operation, supplies the identifier, and returns the resolved record without manual integration glue. Example prompt: Use Jentic to search 'lookup cusip' and execute `/cusip/{cusip}` for each identifier in the analyst's list to produce a unified reference table ## Key endpoints | Method | Path | Description | | --- | --- | --- | | GET | `/cusip/{cusip}` | Resolve a CUSIP to security metadata | | GET | `/cusip/search` | Search the CUSIP database with filters | | GET | `/isin/{isin}` | Resolve an ISIN to CUSIP data | | GET | `/cusipTickerSymbol/ticker/{tickerSymbol}` | Map a ticker to its CUSIP | | GET | `/cusip/loan/search` | Search syndicated loan CUSIPs | | GET | `/cusip/option/{cusip_or_cusipList}` | Resolve option and future CUSIPs | | GET | `/cusip/corporateAction/search` | Search corporate-action records | | GET | `/cusip/vcm/{cusip}` | Resolve a carbon credit CUSIP | ## Key resources - **CUSIP** — Resolve and search CUSIP identifiers, including by ISIN and issuer number - **Loan** — Syndicated loan CUSIP lookup and search - **Option** — Option and future CUSIP lookup and search - **TickerSymbol** — Map exchange tickers to CUSIPs and ISINs - **VCM** — Carbon credit (Voluntary Carbon Market) CUSIP lookup and search ## Why Jentic - **Setup:** Wiring the CUSIP Data API by hand means provisioning an X-API-KEY, attaching it to every header, and mapping its CUSIP, ISIN, and ticker lookup routes yourself. Through Jentic you install once, import the CUSIP Data API from the API Directory, store the key once, and your agent calls it. - **Permission scoping:** CUSIP puts the identifier in the URL path (`/cusip/{cusip}`, `/isin/{isin}`), so a rule can pin your agent to a specific lookup surface. You choose the operations it may call, so if you allow only the identifier and search reads, corporate-action or loan-search calls are not included unless you add them. - **Credential handling:** Your CUSIP X-API-KEY is stored once, encrypted, by your own Jentic One instance and injected at execution time. It never enters the agent's prompt, logs, or context. - **Discovery method:** Agents search Jentic by intent such as 'look up a security by CUSIP' or 'resolve a ticker to a CUSIP', and Jentic returns the matching CUSIP Data operation with its input schema so the agent calls the right endpoint without browsing the reference docs. ## Related APIs - **OpenFIGI API** — Bloomberg's free FIGI identifier mapping covering global instruments - **Polygon.io** — Market data provider that pairs price and quote feeds with reference data - **Finnhub** — Market data and fundamentals provider with ticker and company resolution ## FAQ ### Which OpenAPI specification does this CUSIP Data API page describe? A curated, agent-optimized Jentic specification covering 17 CUSIP Data API operations. CUSIP Global Services also publishes its own OpenAPI document at https://www.cusip.com/swagger/yaml/cusip/api-docs.yaml, which declares OpenAPI 3.0.2 and the same 17 read operations against the same api.cusip.com base URL. The Jentic variant is derived from that document, normalized to OpenAPI 3.0.3, and kept validated so agents can load it directly. Get started with Jentic One, the self-hosted execution layer. ### What authentication does the CUSIP Data API use? The API uses an API key sent in the X-API-KEY request header. Through Jentic the key is held in the encrypted vault and injected at execution time, so the raw key never enters the agent's prompt. ### Can I look up a CUSIP from an ISIN with the CUSIP Data API? Yes. Call GET `/isin/{isin}` for a single ISIN or GET `/isin/{isinList}` for a comma-delimited list. The response returns the corresponding CUSIP records with issuer and issue metadata. ### What are the rate limits for the CUSIP Data API? Rate limits are governed by the CGS commercial agreement and are not encoded in the spec. Limits scale with the licensed data tier; check your CGS contract for the precise quota. ### How do I map a stock ticker to its CUSIP through Jentic? Run pip install jentic, search for 'ticker to cusip', load `/cusipTickerSymbol/ticker/{tickerSymbol}`, and execute it with the ticker. Jentic returns the matching CUSIP and ISIN. ### Does the CUSIP Data API cover syndicated loans and options? Yes. Use `/cusip/loan/{cusip}` and `/cusip/loan/search` for syndicated loans, and `/cusip/option/{cusip_or_cusipList}` and `/cusip/option/search` for options and futures. ### Can I limit what my agent is allowed to do with the CUSIP Data API? Yes. Because you run Jentic One yourself, your own rules decide which CUSIP Data operations and which stored X-API-KEY the agent may use. Since the identifier sits in the URL path, you can pin the agent to specific lookup surfaces such as GET `/cusip/{cusip}` and GET `/isin/{isin}`, or allow only the identifier and search reads. If you grant just those, corporate-action or syndicated-loan search calls stay unavailable to the agent until you explicitly add them.