// company-profile

Spero Therapeutics, Inc.

SPRO
ExchangeNasdaqSectorPharmaceutical PreparationsInc.DEFilings57Insiders13
// api This Spero Therapeutics, Inc. insider-trading data is served live by the Form4API insider trading API. Get the same data via API.

// activity-summary

No insider transactions in the last 30 days.

// 90-day insight

Over the last 90 days, Spero Therapeutics, Inc. insiders sold $63K across 1 transaction with no open-market purchases.

  • Most active insider: Rajavelu Esther with 1 transaction totaling $63K.
  • Largest single sale: $63K by Rajavelu Esther on May 4, 2026.

Activity skews bearish — sales outpace buys.

Institutional Ownership

Top 13F-HR holders of Spero Therapeutics, Inc. as of 2026-03-31

— stable
Total reported AUM
$47.4M
QoQ change
-1.4%
Reporting period
2026-03-31
#1
GSK plc
CIK 1131399
$21.5M
9.2M shares
#2
Pfizer Inc
CIK 78003
$5.5M
2.4M shares
#3
VANGUARD CAPITAL MANAGEMENT LLC
CIK 2100119
$4.2M
1.8M shares

Data source: SEC Form 13F-HR filings. Joined with insider activity above — see who's loading up institutionally while insiders are trading. Full 13F-HR API →

Insider Transactions

Sourced from SEC EDGAR Form 4 filings. Updated hourly.

DateInsiderCompanyTypeSharesPriceValue
May 4, 2026Rajavelu EstherSPRO
Sale
25,240$2.51$63K
Feb 6, 2026Keutzer TimothySPRO
Sale
18,652$2.36$44K
Feb 6, 2026Rajavelu EstherSPRO
Sale
50,816$2.36$120K
Feb 6, 2026Rajavelu EstherSPRO
Sale
37,101$2.36$88K
Feb 4, 2026Keutzer TimothySPRO
Sale
3,471$2.24$8K

45 more transactions hidden

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