Insider cluster buying

Thesis (UNTESTED, blocked on data): When 3+ insiders independently buy within a 30-day window totalling >= $500k, the stock outperforms over the next 30-90 days (Cohen / Malloy / Pomorski 2012).

Code: research/insider_cluster_validate.py Report: research/insider_cluster_report.json (n=0)

Why it failed: The insider_transaction table in db/finance.db has only 44 purchase rows across 19 symbols. The Form-4 ingestion (scripts/build_insider.py) hasn't been run across the universe. Validator is ready to run once the backfill is done.

Verdict: Re-test after running python -m scripts.build_insider. The thesis has strong academic priors and the validator is wired up; this is a "blocked on operational work" rather than a real failure.