Form4insider filings, from the source

Company · CIK 0001701108 · SIC 2834 — Pharmaceutical Preparations · Nasdaq

Spero Therapeutics, Inc. · SPRO

Insider activity reported against this company. All insider holders · On EDGAR ↗

1M3M6M1Y2YAll datashares as filed — not split-adjusted
Open-market buys & salesbuys $22.1M · 7sales $187k · 3net $21.9M
$10k$10k$1M$1M$100M$100MbuyssalesNov 5Dec 17Jan 29Mar 12Apr 24Jun 5Jul 18

Reported at this company — common stock

TradeReported (ET)InsiderSharesAvg priceTotalOwned afterΔ stakeFlags
Aug 3, 2026 AForm 4 →Aug 6, 6:49 pm EDTDebra ZackChief Medical Officer162,311——162,311—10b5-1 late
Jun 23, 2026 AForm 4 →Jun 25, 7:26 pm EDTMilind DeshpandeDirector10,000——101,454—
Jun 23, 2026 AForm 4 →Jun 25, 7:17 pm EDTKathleen TregoningDirector10,000——85,000—
Jun 23, 2026 AForm 4 →Jun 25, 7:14 pm EDTCynthia SmithDirector10,000——85,000—
Jun 23, 2026 AForm 4 →Jun 25, 7:12 pm EDTPatrick V.J.J. VinkDirector10,000——85,000—
Jun 23, 2026 AForm 4 →Jun 25, 6:59 pm EDTFrank E ThomasDirector10,000——85,000—
Jun 23, 2026 AForm 4 →Jun 25, 6:57 pm EDTScott Thomas JacksonDirector10,000——85,000—
Jun 23, 2026 AForm 4 →Jun 25, 6:55 pm EDTJohn C Pottage Jr.Director10,000——85,000—
Jul 17, 2018 PForm 4 →Jul 17, 5:01 pm EDTGLAXOSMITHKLINE PLC10% Owner80,000$12.50$1,000,0001,934,006+4.31% plan?
Jul 5, 2018 SForm 4 →Jul 6, 9:45 pm EDTCristina LarkinChief Operating Officer4,000$17.50$70,0001,500−72.7% plan?
Jul 5, 2018 MForm 4 →Jul 6, 9:45 pm EDTCristina LarkinChief Operating Officer4,000$5.90$23,6005,500— plan?
Jul 5, 2018 SForm 4 →Jul 6, 9:44 pm EDTJoel SendekChief Financial Officer2,000$17.50$35,00015,181−11.6% plan?
Jul 5, 2018 MForm 4 →Jul 6, 9:44 pm EDTJoel SendekChief Financial Officer2,000$5.90$11,80017,181— plan?
Jul 5, 2018 SForm 4 →Jul 6, 9:41 pm EDTAnkit MahadeviaSee Remarks, Director4,676$17.63$82,43765,817−6.63% plan?
Jul 5, 2018 MForm 4 →Jul 6, 9:41 pm EDTAnkit MahadeviaSee Remarks, Director4,676$5.90$27,58867,417— plan?
Nov 6, 2017 PForm 4 →Nov 7, 7:42 pm ESTGLAXOSMITHKLINE PLC10% Owner428,571$14.00$5,999,9941,854,006+30.1% plan?
Nov 6, 2017 CForm 4 →Nov 7, 7:42 pm ESTGLAXOSMITHKLINE PLC10% Owner1,425,435——1,425,435— plan?
Nov 6, 2017 PForm 4 →Nov 7, 4:08 pm ESTJean Francois FormelaDirector428,571$14.00$5,999,9942,408,128+21.6% plan?
Nov 6, 2017 CForm 4 →Nov 7, 4:08 pm ESTJean Francois FormelaDirector1,936,776——1,979,557— plan?
Nov 6, 2017 PForm 4 →Nov 7, 4:06 pm ESTVikas GoyalDirector428,571$14.00$5,999,9941,854,006+30.1% plan?
Nov 6, 2017 CForm 4 →Nov 7, 4:06 pm ESTVikas GoyalDirector1,425,435——1,425,435— plan?
Nov 6, 2017 PForm 4 →Nov 7, 4:05 pm ESTJoel SendekChief Financial Officer5,000$14.00$70,00015,181+49.1% plan?
Nov 6, 2017 CForm 4 →Nov 7, 4:05 pm ESTJoel SendekChief Financial Officer10,181——10,181— plan?
Nov 6, 2017 PForm 4 →Nov 7, 4:05 pm ESTCristina LarkinChief Operating Officer1,500$14.00$21,0001,500— plan?
Nov 6, 2017 PForm 4 →Nov 7, 4:05 pm ESTCasper BreumDirector214,285$14.00$2,999,9901,091,774+24.4% plan?
Nov 6, 2017 CForm 4 →Nov 7, 4:05 pm ESTCasper BreumDirector877,489——877,489— plan?

Reported at this company — derivatives (options, RSUs, warrants)

TradeReported (ET)InsiderSharesAvg priceTotalOwned afterΔ stakeFlags
Aug 3, 2026 AForm 4 →Aug 6, 6:49 pm EDTDebra ZackChief Medical Officer324,675——324,675—10b5-1 late
Jun 23, 2026 AForm 4 →Jun 25, 7:26 pm EDTMilind DeshpandeDirector20,000——20,000—
Jun 23, 2026 AForm 4 →Jun 25, 7:17 pm EDTKathleen TregoningDirector20,000——20,000—
Jun 23, 2026 AForm 4 →Jun 25, 7:14 pm EDTCynthia SmithDirector20,000——20,000—
Jun 23, 2026 AForm 4 →Jun 25, 7:12 pm EDTPatrick V.J.J. VinkDirector20,000——20,000—
Jun 23, 2026 AForm 4 →Jun 25, 6:59 pm EDTFrank E ThomasDirector20,000——20,000—
Jun 23, 2026 AForm 4 →Jun 25, 6:57 pm EDTScott Thomas JacksonDirector20,000——20,000—
Jun 23, 2026 AForm 4 →Jun 25, 6:55 pm EDTJohn C Pottage Jr.Director20,000——20,000—
Jan 2, 2019 AForm 4 →Jan 2, 7:23 pm ESTThomas R Parr Jr.Chief Scientific Officer35,000——35,000—
Jan 2, 2019 AForm 4 →Jan 2, 7:20 pm ESTDavid A. MelnickChief Medical Officer65,000——65,000—
Jan 2, 2019 AForm 4 →Jan 2, 7:18 pm ESTCristina LarkinChief Operating Officer65,000——65,000—
Jan 2, 2019 AForm 4 →Jan 2, 7:16 pm ESTJoel SendekChief Financial Officer65,000——65,000—
Jan 2, 2019 AForm 4 →Jan 2, 7:12 pm ESTAnkit MahadeviaCEO and President, Director180,000——180,000—
Sep 21, 2018 AForm 4 →Sep 21, 5:38 pm EDTJohn C Pottage Jr.Director12,146——12,146—
Jul 5, 2018 MForm 4 →Jul 6, 9:45 pm EDTCristina LarkinChief Operating Officer4,000——20,434—
Jul 5, 2018 MForm 4 →Jul 6, 9:44 pm EDTJoel SendekChief Financial Officer2,000——165,833—
Jul 5, 2018 MForm 4 →Jul 6, 9:41 pm EDTAnkit MahadeviaSee Remarks, Director4,676——118,888—
Jun 5, 2018 AForm 4 →Jun 6, 8:02 pm EDTFrank E ThomasDirector6,073——6,073—
Jun 5, 2018 AForm 4 →Jun 6, 8:01 pm EDTJean Francois FormelaDirector6,073——6,073—
Jun 5, 2018 AForm 4 →Jun 6, 8:01 pm EDTDavid P SouthwellDirector6,073——6,073—
Jun 5, 2018 AForm 4 →Jun 6, 8:01 pm EDTCasper BreumDirector6,073——6,073—
Jun 5, 2018 AForm 4 →Jun 6, 8:00 pm EDTMilind DeshpandeDirector6,073——6,073—
Jun 5, 2018 AForm 4 →Jun 6, 8:00 pm EDTPatrick V.J.J. VinkDirector6,073——6,073—
Mar 30, 2018 AForm 4 →Mar 30, 5:30 pm EDTDavid P SouthwellDirector12,146——12,146—
Jan 4, 2018 AForm 4 →Jan 5, 10:11 am ESTDavid A. MelnickChief Medical Officer135,000——135,000—
Dec 13, 2017 AForm 4 →Dec 15, 4:07 pm ESTCristina LarkinChief Operating Officer62,540——62,540—
Dec 13, 2017 AForm 4 →Dec 15, 4:06 pm ESTJoel SendekChief Financial Officer27,795——27,795—
Dec 13, 2017 AForm 4 →Dec 15, 4:05 pm ESTThomas R Parr Jr.Chief Scientific Officer36,134——36,134—
Dec 13, 2017 AForm 4 →Dec 15, 4:05 pm ESTAnkit MahadeviaSee Remarks, Director125,079——125,079—
Nov 6, 2017 CForm 4 →Nov 7, 7:42 pm ESTGLAXOSMITHKLINE PLC10% Owner7,399,735——0—
Nov 6, 2017 CForm 4 →Nov 7, 4:08 pm ESTJean Francois FormelaDirector10,507,362——0—
Nov 6, 2017 CForm 4 →Nov 7, 4:06 pm ESTVikas GoyalDirector7,399,735——0—
Nov 6, 2017 CForm 4 →Nov 7, 4:05 pm ESTJoel SendekChief Financial Officer61,880——0—
Nov 6, 2017 CForm 4 →Nov 7, 4:05 pm ESTCasper BreumDirector4,320,936——0—