MGNX · Insider Trading

MacroGenics, Inc.

Every open-market purchase and sale reported by MGNX officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.

Form 4 Filings
50
most recent
Open-Market Buys
1
code P
Sales
1
code S
Reporting Insiders
16
current holders
MGNX — Recent Form 4 Transactions (latest 2026-10-07)
FiledInsiderRole TypeSharesValue
2026-10-07 Ezio Bonvini Sr VP, Research & CSO M +8,000 +$20.80K
2026-08-20 Jeffrey Stuart Peters Senior VP, GC, and Secretary Sell −31,105 −$129.09K
2026-08-18 Ezio Bonvini Sr VP, Research & CSO M +40,000 +$104.00K
2026-05-20 Margaret Liu Director M +3,750 —
2026-05-20 Scott Thomas Jackson Director M +3,750 —
2026-05-20 Jay Philip Siegel Director M +3,750 —
2026-05-20 Federica F. O'Brien Director M +3,750 —
2026-05-20 Karen Jean Ferrante Director M +3,750 —
2026-05-20 Scott Koenig Director A +25,750 deriv. —
2026-05-20 William K Heiden Director M +3,750 —
2026-05-20 Meenu Chhabra Director M +3,750 —
2026-05-20 Edward Hurwitz Director M +3,750 —
2026-05-20 David C Stump Director M +3,750 —
2026-02-17 Beth Ann Smith VP, Controller & Treasurer MIXED +672 −$723
2026-02-17 Jeffrey Stuart Peters Senior VP, GC, and Secretary MIXED +8,185 −$8.80K
2026-02-17 Thomas Spitznagel Sr VP, Technical Ops MIXED +7,812 −$9.44K
2026-02-17 Scott Koenig Director M +21,165 —
2026-02-17 James Karrels SVP and CFO MIXED +9,209 −$9.90K
2026-02-17 Eric Blasius Risser President and CEO MIXED +10,232 −$11.00K
2026-02-17 Ezio Bonvini Sr VP, Research & CSO MIXED +10,232 −$11.00K
2026-02-10 Beth Ann Smith VP, Controller & Treasurer MIXED +2,577 −$2.94K
2026-02-10 Scott Koenig Director M +15,831 —
2026-02-10 Eric Blasius Risser President and CEO MIXED +10,948 −$12.46K
2026-02-10 James Karrels SVP and CFO MIXED +10,027 −$11.41K
2026-02-10 Jeffrey Stuart Peters Senior VP, GC, and Secretary MIXED +9,209 −$10.48K
2026-02-10 Ezio Bonvini Sr VP, Research & CSO MIXED +11,153 −$12.70K
2026-02-10 Thomas Spitznagel Sr VP, Technical Ops MIXED +9,329 −$10.26K
2025-12-10 Beth Ann Smith VP, Controller & Treasurer A +25,000 deriv. —
2025-08-21 William K Heiden Director Buy +100,000 +$150.51K
2025-08-19 Thomas Spitznagel Sr VP, Technical Ops A +30,000 deriv. —
2025-08-19 Jeffrey Stuart Peters Senior VP and General Counsel A +30,000 deriv. —
2025-08-15 Eric Blasius Risser President and CEO A +550,000 deriv. —
2025-08-15 Scott Koenig Director M +52,829 —
2025-05-22 Margaret Liu Director M +6,500 —
2025-05-22 Meenu Chhabra Director M +6,500 —
2025-05-22 Scott Thomas Jackson Director M +6,500 —
2025-05-22 Federica F. O'Brien Director M +6,500 —
2025-05-22 William K Heiden Director M +6,500 —
2025-05-22 Jay Philip Siegel Director M +6,500 —
2025-05-22 David C Stump Director M +6,500 —
2025-05-22 Karen Jean Ferrante Director M +6,500 —
2025-05-22 Edward Hurwitz Director M +6,500 —
2025-02-19 James Karrels SVP, CFO and Secretary MIXED +9,208 −$14.82K
2025-02-19 Ezio Bonvini Sr VP, Research & CSO M +16,665 —
2025-02-19 Stephen L. Eck Chief Medical Officer MIXED +11,723 −$12.65K
2025-02-19 Eric Blasius Risser Chief Operating Officer MIXED +10,232 −$16.47K
2025-02-19 Scott Koenig President and CEO M +42,329 —
2025-02-19 Beth Ann Smith VP, Controller & Treasurer MIXED +672 −$1.08K
2025-02-19 Jeffrey Stuart Peters Senior VP and General Counsel MIXED +8,185 −$13.18K
2025-02-19 Thomas Spitznagel Sr VP, Technical Ops MIXED +7,812 −$14.13K
MGNX — Current Insider Holders
InsiderRole Shares HeldValue
Edward Hurwitz Director 1,752,820 $3.84M
Scott Koenig President and CEO 1,294,720 $2.84M
James Karrels SVP and CFO 306,368 $670.95K
Ezio Bonvini Sr VP, Research & CSO 193,799 $424.42K
William K Heiden Director 114,750 $251.30K
Eric Blasius Risser President and CEO 83,602 $183.09K
Thomas Spitznagel Sr VP, Technical Ops 38,543 $84.41K
Stephen L. Eck Chief Medical Officer 29,377 $64.34K
Federica F. O'Brien Director 14,750 $32.30K
David C Stump Director 14,750 $32.30K
Margaret Liu Director 14,750 $32.30K
Meenu Chhabra Director 14,750 $32.30K
Scott Thomas Jackson Director 14,750 $32.30K
Karen Jean Ferrante Director 14,750 $32.30K
Jay Philip Siegel Director 14,750 $32.30K
Beth Ann Smith VP, Controller & Treasurer 12,781 $27.99K
MGNX Insider Trading FAQ
Who are the insiders at MGNX?
16 officers, directors and 10%+ beneficial owners currently report holdings in MGNX via SEC Form 4.
Are MGNX insiders buying or selling?
Across the 50 most recent Form 4 filings for MGNX, 1 were open-market purchases (code P) and 1 were sales (code S). Sales frequently reflect scheduled 10b5-1 plans or tax withholding rather than a view on the stock.
How current is MGNX insider data?
Form 4 must be filed within two business days of the transaction, so this is close to real time. The most recent MGNX filing is dated 2026-10-07.
How to read Form 4 activity

Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.

Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.

Full filing history and per-insider positions are on the MGNX quote page; the site-wide leaderboard is on the insider transactions hub.

Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.