The ranking measure: Ranked by net opportunistic insider buying over the last six months: open-market purchases (Form 4 code P) minus open-market sales (code S) by insiders classed as opportunistic, in basis points of market value (third-party market data). Following Cohen, Malloy and Pomorski (2012), an insider who traded in the same calendar month in each of the three previous calendar years is routine; one who traded in each of those years without a repeating month is opportunistic. Insiders without a trade in each of the three years can't be classified: their purchases are shown but not ranked. Trades marked as made under a Rule 10b5-1 plan are left out. Our Form 4 record starts in late 2022.

Who is included: At least one opportunistic open-market purchase in the last six months; revenue of at least $100M; market value available; not a bank, insurer or REIT.

Market values are from third-party market data as of 2026-11-02 and may be delayed; every other figure comes from SEC filings.

A new edition is published each calendar quarter; past editions are kept unchanged. Observations, not recommendations — a position on this ranking is a description of reported figures, never advice.

Research cited

  • Cohen, L., Malloy, C., & Pomorski, L. (2012). Decoding inside information. Journal of Finance.
  • Lakonishok, J., & Lee, I. (2001). Are insider trades informative?. Review of Financial Studies.