# Insider Flow > Aggregate SEC Form 4 insider activity for a ticker over a caller-supplied lookback window, classify each transaction by SEC transaction code and Rule 10b5-1 status, separate signal (conviction buys, discretionary sales) from noise (grants, exercises, tax withholding, 10b5-1 sales), detect cluster buys (>= 2 insiders in a 14-day window worth >= $100k), and emit a sentiment label backed by the underlying dollar flow. Use when a PM or fundamental analyst asks "are insiders buying or selling this name?" Uses Massive's pre-parsed Form 4 endpoint. Requires Stocks Basic. Runs on the free tier. - Skill: `rgourley/insider-flow` (Agent Skill, multi-file: 7 files) - Install (CLI): `npx skillmds@latest add rgourley/insider-flow` - Raw SKILL.md: https://api.skillmd.com/api/skills/rgourley/insider-flow/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: rgourley (https://skillmd.com/u/rgourley) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/rgourley/insider-flow --- # insider-flow You hand over a ticker. The skill pulls every Form 4 filed against the issuer over the lookback window, classifies each transaction, separates the signal (open-market buys, non-scheduled sales) from the noise (grants, option exercises, 10b5-1 scheduled sales), detects cluster buys, and emits a sentiment label backed by the underlying dollar flow. The point is to answer the question a PM actually asks: **are insiders buying or selling this name, and does it matter?** The default read ignores 10b5-1 sales (pre-committed months in advance) and comp-related grants because they carry no signal about what management thinks of the current price. ## When to invoke - A PM asks "any insider activity on NVDA in the last 6 months?" - A fundamental analyst wants a heads-up on the CEO's stock transactions over a cycle - Screening a watchlist for cluster buys as a bullish overlay on weakness - The user says "insider flow", "Form 4 activity", "who's buying / selling", "insider signal" Not for: real-time (Form 4 is filed within 2 business days, so this is days-fresh, not tick-fresh). Not for 13-F holdings (institutional ownership is a separate skill). ## What you need - A ticker (`--ticker`, required) - `MASSIVE_API_KEY` exported in the environment - Stocks Basic plan minimum. The `/stocks/filings/vX/form-4` endpoint is included on every Stocks plan. Optional: - `--lookback-days` (default 180): calendar-day window back from today. - `--exclude-directors`: drop pure-director rows (`is_director` AND NOT `is_officer` AND NOT `is_ten_percent_owner`). Useful for names with VC or PE board reps unwinding a fund position, which structurally look bearish but carry no operator signal. Executives who also sit on the board are kept (they carry operator signal). ## What you get back Two output layers from one run. **Layer 1: canonical JSON** matching [`output-schema.json`](./output-schema.json). Top-level `summary` (sentiment label + reasoning, conviction buy / discretionary sale / scheduled sale / routine comp counts and dollars, net conviction flow), `clusters[]` (detected 14-day cluster buy windows sorted by dollar volume), `notable_buys[]` (top 5 open-market buys by dollar), `notable_sales[]` (top 5 discretionary sales), `by_role` (aggregate flow keyed on officer / director / 10% owner). **Layer 2: rendered note**. Sentiment label at the top, transaction- flow block, cluster buys (when detected), notable individual transactions, by-role aggregation, one-line Take. See [`references/rendering.md`](./references/rendering.md). ## How it works 1. **Pull Form 4 rows** via `GET /stocks/filings/vX/form-4?tickers={T}&filing_date.gte={from_date}&limit=1000&sort=filing_date.desc`. Massive returns one row per transaction leg (a single Form 4 filing can have multiple non-derivative + derivative legs). 2. **Classify each row** by SEC transaction code + Rule 10b5-1 status. See [`references/transaction-codes.md`](./references/transaction-codes.md) for the full mapping: - `conviction_buy`: code P (open-market purchase, non-derivative) - `discretionary_sale`: code S with `aff_10b5_one=false` - `scheduled_sale`: code S with `aff_10b5_one=true` - `routine_comp`: codes A (grant), M (derivative exercise), F (tax withholding) - `non_informative`: everything else (gifts, expiries, swaps) 3. **Detect cluster buys.** Rolling 14-day windows where >= 2 distinct insiders made open-market purchases (code P) summing to >= $100k. One entry per detected cluster. 4. **Aggregate by role.** Officer / director / 10% owner net flow. Officers dominate signal typically; 10% owners can be activists or founders with idiosyncratic reasons. 5. **Emit sentiment** on the net conviction flow (buys minus discretionary sales, 10b5-1 sales excluded). Buckets: - `strong_bullish`: cluster detected + positive net, or net > $250k - `bullish`: net > $50k - `neutral`: between -$250k and +$50k - `bearish`: net < -$250k - `strong_bearish`: net < -$1M ## Foundations used - [`massive-api-patterns`](../massive-api-patterns) for REST auth, retry, and pagination on the filings endpoint. ## Output mode: note Narrative note. Insider activity for a single name is a small number of rows (typically 50-300 in six months for an active name); a wide table would waste space. The rendered format optimizes for a PM reading the note once and either dismissing (no signal), noting a cluster buy, or noting a specific insider's discretionary sale. ## Endpoints used - `GET /stocks/filings/vX/form-4?tickers={T}&filing_date.gte={D}` Every Form 4 row for the ticker since `D`. Paginated; one call per page. ## Doesn't handle (yet) - **Cross-ticker roll-up.** A watchlist mode ("scan my 30 names for cluster buys this week") would compose this skill and aggregate. Queued. - **Base rate context.** No per-name "typical monthly volume of discretionary sales" percentile. A $2M sale is different for JPM than for MU. Queued. - **Price context.** No overlay of transaction date vs price. Insider buys near 52-week lows are stronger signal; sales at highs are weaker signal. Queued as a chain with `technical-briefing`. - **10b5-1 plan adoption date.** The endpoint returns `aff_10b5_one` as a boolean but not when the plan was adopted. Plans adopted right before a material corporate event are themselves a red flag; that data is in footnotes but requires text parsing. - **13-D / 13-G triggers.** Not covered; those are institutional filings on a different form. These are clean PR extensions. The output schema is forward-compatible.