Official Data and Filing Sources

Reviewed against first-party guidance on 2026-10-01. API rules can change: recheck the linked terms and limits before automated or high-volume use. The bundled scripts do not call these services and do not require API keys. This is a routing and metadata guide, not an executed API client: documentation review does not establish authenticated retrieval or current service availability.

Routing by claim

Start with the original authority most fit for the claim:

• company financials and risk disclosures: the jurisdiction's official filing system, then the filed document;
• establishment, employment, prices, production, trade, population, and GDP: the responsible national statistical office or central bank;
• rules, approvals, enforcement, licenses, and consultations: the responsible regulator or official legal gazette;
• cross-country indicators: the original national source when comparability is not required; otherwise an international harmonized dataset with metadata;
• classifications: the current official NAICS, NACE, ISIC, product, trade, or sector taxonomy and its correspondence tables.

Do not treat an aggregator as an independent corroborating source when it reproduces the same underlying series.

United States

SEC EDGAR and company filings

• SEC Developer Resources documents company submissions and extracted XBRL data APIs.
• Accessing EDGAR Data requires a declared user agent and states a current maximum of 10 requests per second across the user's machines. Download only what is needed.
• EDGAR filings can be corrected or removed after acceptance. Record accession number, form, filing date, reporting period, amendment status, exact table or XBRL fact, units, and retrieval date.
• Consolidated company revenue is not automatically market revenue. Remove out-of-scope products/geographies and avoid summing parent/subsidiary or channel/end-customer values twice.

U.S. Census Bureau

• The Census Data API User Guide links data to a geographic boundary and a dataset vintage.
• As revised 2026-05-14, the query-limits page permits up to 50 variables per query and requires a key for all data queries. The key page describes free registration. The key travels in the query URL; redact key before storing source URLs, logs, or request provenance. Never place a key in a report, source ledger, or bundled script.
• Use program-specific methodology, margins of error, universe, geography, and vintage. ACS estimates, Population Estimates, and decennial counts are not interchangeable.
• The 2022 Economic Census methodology defines the target population, sampling frame, exclusions, administrative data, imputation, disclosure avoidance, and product collection.
• The NAICS site identifies 2022 NAICS as the current published structure while a 2027 revision process is underway. Store the version used.

Bureau of Labor Statistics

The BLS API FAQ, last modified 2023-08-30, documents:

• registered v2: 500 queries/day, 50 series/query, 20 years/query;
• unregistered v1: 25 queries/day, 25 series/query, 10 years/query;
• both: 50 requests per 10 seconds;
• v2 registration renewal at least annually;
• v1 returns observations and footnotes without descriptive metadata.

Record series ID, survey/program, seasonal adjustment, units, frequency, footnotes, publication date, and revision status. Consult the program's methodology and release calendar rather than relying on the API response alone. Inspect message and each series' observations even when the response says REQUEST_SUCCEEDED: the FAQ shows invalid-series messages with that status.

Bureau of Economic Analysis

The BEA API User Guide, dated 2026-04-20, requires a registered UserID and documents three rolling per-minute limits:

• 100 requests;
• 100 MB retrieved;
• 30 errors.

BEA returns HTTP 429 and a Retry-After header when throttled. The guide warns that limits may change. Query metadata methods before data, restrict years and dimensions, and avoid broad ALL requests. Record current versus chained dollars, reference year, table/line code, frequency, seasonality, and release vintage. Chained-dollar components may not be additive; use published contributions or current-dollar shares where appropriate. Check BEAAPI.Results.Error as well as HTTP status; request parameters may be echoed in the response, so redact UserID before archiving it.

Federal Reserve and FRED/ALFRED

• FRED API documentation describes v2 bulk release history and v1 series-level FRED/ALFRED access.
• A registered key is required under the FRED API Terms. The reviewed terms do not state one fixed numerical request ceiling; they reserve the right to impose or change limits.
• The terms warn that third parties may own series and impose additional restrictions. Follow the original producer's rights and attribution.
• FRED normally presents latest values; ALFRED preserves real-time vintages. Record source, release, series ID, frequency, units, seasonal adjustment, notes, and vintage dates.

International and harmonized sources

World Bank

The Indicators API documentation states that v2 is current, v1 is discontinued, and API authentication is not required. Preserve indicator code, database/source, source note, source organization, unit, income/region classification vintage, and retrieval date. The WDI catalog publishes metadata and revision-history resources. A World Bank indicator may originate with a national agency or another international organization; retain that lineage.

International Monetary Fund

The IMF Data API page states that IMF data are available through SDMX 2.1 and SDMX 3.0 APIs. Use the dataset's data structure, codelists, unit, scale, frequency, observation status, and methodological metadata. Do not assume similarly named indicators across IMF datasets have identical definitions. Use the current API portal linked on that page (its Swagger explorer requires portal sign-in) to select a data service and verify its access requirements. The separate SDMX Central guide concerns structure, validation, conversion, and registration services; it does not establish a data-download endpoint contract.

OECD

The OECD Data Explorer API guide, published 2025-04-30, describes the SDMX API, free access subject to OECD terms, and rate limiting without publishing one universal numerical ceiling on that page. It warns that omitting a dataflow version selects the latest version and that later structures may not be backward compatible. Store agency, dataset, dataflow version, dimensions, codes, attributes, and query.

Eurostat

The Eurostat API introduction documents Statistics, SDMX 2.1, SDMX 3.0, catalogue, and asynchronous services. It states that datasets are updated twice daily when changes are available and that the database contains only the latest version, without past-version documentation. Preserve the retrieved file and update timestamp when a reproducible vintage matters.

The ESS quality and metadata handbook is a standard for reporting source, process, quality, and metadata. Record flags, breaks, seasonal adjustment, units, NUTS/geography version, and dataset code.

Other national statistical agencies

Use the relevant country's official agency before secondary compilations. Examples of current first-party interfaces:

• Statistics Canada Web Data Service provides data and metadata. Guide revision 1.6 (2025-01-24) documents a 50-request/second server limit and 25-request/second individual IP limit, and possible HTTP 409 responses during update windows.
• The UK ONS Developer Hub describes an open, no-key beta API. It warns that breaking changes can occur; store dataset, edition, and version because new versions reflect corrections, revisions, or new data.

For any country, confirm:

1. the official statistics producer and legal mandate;
2. release calendar, methodology, quality statement, and revision policy;
3. classification and geography versions;
4. API/download terms and current operational limits;
5. whether the dataset is official, experimental, modeled, or an administrative extract.

Industry and product classifications

• NAICS classifies establishments by primary economic activity; it is not itself a product-market definition.
• NACE Rev. 2.1 began feeding European statistics from 2025. Use the 2025 manual and correspondence tables when comparing Rev. 2 and Rev. 2.1.
• Product classifications (NAPCS, CPA, PRODCOM, CPC, HS/CN) may fit market outputs better than an establishment-based industry code.
• A concordance can be one-to-many or many-to-many. Never apply it as a lossless conversion without weights and uncertainty.

API handling rules

• Use APIs only during research, with user-approved network access.
• Keep credentials outside reports and scripts; never commit keys.
• Respect official terms, user-agent requirements, rate limits, retries, and bulk-download guidance.
• Cache lawful downloads, record the exact query and retrieval time, and avoid repeatedly requesting unchanged data.
• Validate response status, metadata, units, flags, suppression, and missing values before analysis.
• Treat current limits in this file as a dated snapshot, not a permanent entitlement.