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Margaret A Horn

CIK 1294192 · Chief Operating Officer · last filed 2026-06-17

Margaret A Horn is a Chief Operating Officer who has filed 72 SEC Form 4 insider transactions across 4 companies since 2007. The most recent filing, for RVMDW, was dated Jun 17, 2026. Across all open-market trades the lifetime net is −$36.8M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $21.1M across reported positions.

"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.

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Disclosed Exposure

$21.14M

Companies

4

Total Filings

72

Lifetime Open-Market Net

-$36.84M

Holdings By Company

Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
Symbol Role Shares Price Disclosed Exposure Lifetime OM Net Filings Latest Filed
RVMDW Chief Operating Officer 218,622 $8.84 $1.93M -$29.60M 19 2026-06-17
SANGAMO THERAPEUTICS, INC (SGMO) Delisted Director 82,650 $0.18 $14.7K $0 4 2025-06-16
RVMD Chief Operating Officer 104,460 $183.86 $19.21M -$7.24M 23 2023-10-25
KOSAN BIOSCIENCES INC (KOSN) Delisted SVP, General Counsel — — — $0 1 2007-01-04

Recent Filings

72 filings
Insider activity across all companies, newest first. Form 4 rows are post-trade confirmations (buys, sells, grants, exercises). Notice (144) rows are pre-trade notices of intent to sell restricted or control stock under Rule 144 — they may not all execute. Compare adjacent dates to see which notices became actual sales.
Filed Symbol Action Net Shares Net $ Link
2026-06-17 RVMDW Mixed −3,575 -$12.20M EDGAR
2026-06-15 RVMD Notice (144) −90,000 -$13.85M EDGAR
2026-06-15 RVMDW Mixed — -$1.07M EDGAR
2026-06-15 RVMD Notice (144) −3,486 -$536.4K EDGAR
2026-06-11 RVMD Notice (144) −10,000 -$1.44M EDGAR
2026-03-19 RVMDW Sell (S) −4,583 -$455.9K EDGAR
2026-03-13 RVMD Notice (144) −4,722 -$470.3K EDGAR
2026-03-03 RVMDW Grant (A) +21,100 $0 EDGAR
2026-01-09 RVMDW Mixed — -$4.66M EDGAR
2026-01-07 RVMD Notice (144) −75,000 -$5.99M EDGAR
Showing 1–10 of 72
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Form 4 codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.