Form 10-K Financial Statements (and Every Other SEC Filing We Read So You Don’t Have To)

When you load Apple's revenue history, peek at Microsoft's balance sheet, or run a discounted cash flow on Costco, the numbers ultimately come from one filing: Form 10-K. The income statement, the balance sheet, and the cash flow statement — the financial statements every fundamentals API on the planet sells you — live in this single annual filing every public US company submits to the SEC.

The 10-K is the headliner, but it is one of about twenty SEC forms that carry essentially every public-market data point a developer actually uses: fundamentals, insider trades, fund holdings, executive comp, IPO terms, delistings. StockFit reads all of them so you do not have to touch a single line of XBRL or SGML. This post is the field guide. For every form we ingest, you get a one-line plain-English explanation, the actual data we pull out of it, and the exact StockFit API endpoint that serves it. If you have ever asked yourself “okay but where does the dividend history actually come from?” — answer below. (Spoiler: it's an N-CSR, not the company's 10-K.)

Form 10-K financial statements: the annual report that anchors everything

The Form 10-K is the SEC's annual report — a comprehensive disclosure every public US company has to file once per fiscal year, usually 60 to 90 days after year-end. Three of its sections do most of the heavy lifting for fundamentals work: the audited income statement, balance sheet, and cash flow statement. Around those sit segment results, risk factors, MD&A, executive bios, accounting policies, and share count.

Every line item is tagged in XBRL, the SEC's structured-data format. We run each 10-K through Arelle, normalize the tags onto a stable canonical schema (so revenue is revenue across every issuer, regardless of which XBRL concept they used), classify the period, and store the raw fact alongside our curated standardized version. A typical 10-K contains six to ten thousand facts; we surface the ones that matter and keep the rest queryable for power users.

Restatements are first-class: when a company files a 10-K/A correcting last year's numbers, our pipeline keeps the per-fact, per-amendment audit trail so you can roll the financial statements back to what the market actually saw on any given Tuesday.

curl "https://api.stockfit.io/v1/api/financials/income-statement?symbol=AAPL&period=annual&limit=10" \
  -H "Authorization: Bearer YOUR_API_KEY"

That single call replays ten years of Apple's 10-K income statement, structured, deduplicated, amendment-aware. Behind it: ten 10-K filings parsed, ~70,000 XBRL facts mapped to the canonical schema, every restatement applied with full provenance.

Form 10-Q and Form 20-F: quarterly and foreign-issuer counterparts

The 10-K's siblings cover the gaps. Form 10-Q reports the same line items quarterly (unaudited, filed 40–45 days after each quarter-end). Form 20-F is the 10-K equivalent for foreign private issuers — ADRs, dual-listed companies, non-US headquartered firms like ASML, TSMC, and Spotify. Both feed the same fundamentals endpoints.

Form 8-K: every material event, classified by item code

If something happens to a public company between quarterly reports — a CEO resigns, an acquisition closes, earnings get pre-released, a credit facility is amended — the SEC requires an 8-K within four business days. Each 8-K is tagged with one or more item codes (1.01, 2.02, 5.02, etc.) that tell you what kind of event it is.

We parse the SEC submission header to extract every item code on the filing, then expose them so you can build event-driven workflows: filter for 2.02 to grab earnings releases, 5.02 for executive departures, 1.01 for material agreements, 8.01 for catch-all material disclosures.

IPO forms: S-1 and EFFECT

When a company wants to go public, it files Form S-1 — the IPO prospectus. It is a long document (often 200+ pages) covering the use of proceeds, financial history, risk factors, ownership structure, and the offering itself. Companies file amendments (S-1/A) repeatedly as they iterate with the SEC, each one updating price ranges, share counts, underwriter syndicates.

The actual effective date — the day the SEC clears the registration so trading can begin — lives in a separate filing called EFFECT. We pair the two: S-1 for the offering details, EFFECT (the first one per CIK) as the IPO date proxy.

Form 25-NSE: the authoritative delisting signal

When a stock leaves an exchange, the exchange itself files Form 25 (specifically the 25-NSE variant). This is the only authoritative delisting source — not third-party scraping, not vendor classifications. The form carries a signature date that becomes the official delisted_at for the company.

Why this matters: companies often continue filing with the SEC after getting delisted (for deregistration paperwork, OTC trading), and most data vendors confuse the two. We do not. If 25-NSE has not been filed, the stock is still listed.

Insider transactions: Forms 3, 4, and 5

Section 16 of the Exchange Act requires officers, directors, and 10%+ shareholders to disclose their ownership of company stock. They file Form 3 when they first take office (initial disclosure), Form 4 every time they buy or sell (within two business days), and Form 5 once a year as a catch-up for anything that should have been on a 4 but slipped.

Each Form 4 carries a transaction code: P for open-market purchase, S for open-market sale, A for grant/award, M for option exercise, F for tax withholding, plus a dozen others. The code is the difference between “the CFO loaded up” and “the CFO sold to pay taxes on a vesting grant” — surface-level transaction count is meaningless without it.

Schedule 13D and 13G: 5%+ beneficial ownership

Anyone — person, fund, family office — who acquires more than 5% of a public company's shares has to disclose it. They pick one of two flavors based on intent: 13D if they are an active investor (intend to influence management, push for changes, run a proxy fight), 13G if they are passive (index funds, long-term holders).

13D filings are the activist-investor fingerprint. When Carl Icahn or Pershing Square shows up in a name, this is the form. We classify each filing's intent (passive vs. activist) and link it back to the issuer so you can build position-tracking dashboards.

Form 13F-HR: institutional investor holdings every quarter

Any institutional investment manager with at least $100M in qualifying assets has to file Form 13F-HR within 45 days of each quarter-end. These filings are how the public sees what Berkshire Hathaway, Renaissance Technologies, Bridgewater, Fidelity, and every other major fund actually owns — right down to position sizes by CUSIP.

Caveats: 13F is US long equities only (no shorts, no derivatives, no foreign listings), it's 45 days stale, and managers can request confidentiality on positions. But within those bounds it is the deepest free dataset on institutional positioning anywhere.

The fund world: NPORT-P, N-CEN, N-1A, N-CSR

ETFs and mutual funds file an entirely different set of forms than operating companies do. If you are working with funds, this is where the gold is — and the data quality gap between StockFit and most fund-data vendors is widest, because most vendors stop at the prospectus.

Proxy statements: DEF 14A and DEFA14A

Once a year, ahead of the annual shareholder meeting, every public company files a proxy statement (DEF 14A). This is the document that asks shareholders to vote on board nominees, executive compensation packages, auditor ratification, and any shareholder proposals. It is also where the SEC requires disclosure of named-executive-officer compensation, peer groups, and pay-versus-performance tables.

DEFA14A is the “additional materials” companion — companies file these to amend or supplement an already-distributed proxy. We process both to extract the structured comp data, including the pay-versus-performance economics that became required disclosures starting in 2023.

ARS: the glossy companion to the 10-K

The Annual Report to Shareholders (ARS) is the narrative version of the 10-K — the photo-heavy, designed PDF that shareholders actually read. It is technically a separate filing and contains material that is not in the 10-K itself: the CEO letter, branded charts, segment narratives, ESG disclosures.

We index it for document retrieval, even though most of the structured fundamentals data lives elsewhere. If you are doing LLM-based research that needs the actual narrative, the ARS is where to find management's voice in their own words.

FAQ

Where to start

If you are building anything that touches public-company data, the answer to “where does this come from?” is almost always one of the forms above. The free tier of the StockFit API gives you direct access to every endpoint linked in this post — fundamentals, insider trades, fund holdings, executive comp, IPOs, delistings.

Two recommended next reads: Converting XBRL Financials to JSON for Backtesting if you want to understand how the 10-K and 10-Q pipelines actually work, and A Deep Lens on Any ETF if you are working with funds and want to see NPORT-P / N-CEN in practice.

Or just grab a key and start poking. The API will surprise you with how much is in there.