insider-dedup

Deduplicate overlapping SEC insider filings to compute accurate holdings and activity.

Updated Apr 29, 2026
One-click install
npx skills add https://github.com/jefrnc/quant-llm-skills --skill insider-dedup
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: insider-dedup
Source: https://github.com/jefrnc/quant-llm-skills/tree/main/skills/insider-dedup
Command: npx skills add https://github.com/jefrnc/quant-llm-skills --skill insider-dedup

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This Skill prevents inflated insider holdings and insider transaction counts caused by double-counting overlapping Schedule 13D/13G group filings and closely related Form 3/4/5/144 transactions.

Core Features & Use Cases

  • Group and joint-filer deduplication: Treats related 13D/13G filings as one per-share position when the filings indicate shared group membership or joint reporting.
  • Shared voting/dispositive power attribution: Counts shared-power shares once even when multiple filers report the same underlying position.
  • Transaction-level dedup for Form 4: Identifies identical-tuple transactions reported by multiple related parties (e.g., executive, trust/LLC, spouse/dependent) and sums only the deduped economic events.
  • Special-case guards: Excludes Form 144 from completed-sale tallies and avoids mixing unrelated filing types like 13F with 13D/13G ownership logic.
  • Event-series correctness: Uses amendment-chain “latest holding” semantics per deduped group when building holdings and reconciles with expected deal/dilution signals.

Quick Start

Use insider-dedup to compute a deduplicated total insider holdings percentage from all 13D/13G (and amendments) for a given issuer within your target date window.

Frequently Asked Questions about insider-dedup

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I deduplicate overlapping SEC insider filings to compute accurate insider ownership?▼

Deduplicating overlapping SEC insider filings requires treating related Schedule 13D/13G group filings as a single position and matching identical Form 4 transactions across joint filers. This prevents inflated insider holdings and transaction counts caused by double-counting shared voting or dispositive power.

Why does my insider ownership calculation show inflated holdings from Schedule 13D group filings?▼

Inflated insider holdings from Schedule 13D group filings occur when multiple joint filers report the same underlying shares. Applying group identity and shared voting/dispositive power rules counts shared-power shares once per deduped group, ensuring accurate ownership aggregation.

How do I reconcile Form 4 transactions across multiple related parties like trusts and spouses?▼

Reconciling Form 4 transactions across related parties involves identifying identical-tuple transactions reported by executives, trusts, or spouses and summing only the deduped economic events. This transaction-attribution matching prevents double-counting insider activity within a group.

Does Form 144 count as an insider sale when reconciling SEC transaction filings?▼

Form 144 does not count as a completed insider sale in transaction tallies. It is explicitly excluded from completed-sale counts to avoid mixing with actual Form 4 sales and to maintain accurate insider activity reconciliation.

How do I apply amendment-chain latest holding semantics when aggregating Schedule 13D filings?▼

Applying amendment-chain latest holding semantics uses the most recent amendment per deduped group to build current insider holdings. This ensures event-series correctness by reconciling the latest reported position with expected deal or dilution signals.

Can I mix 13F filings with 13D and 13G ownership logic for data reconciliation?▼

Mixing 13F filings with 13D and 13G ownership logic is avoided because they represent different reporting contexts. The deduplication process applies special-case guards to prevent mixing unrelated filing types and ensure accurate beneficial ownership computation.