What is SPRO's dilution risk score?

SPRO has a latest available DilutionScore record of 26/100, categorized as medium dilution risk by the DilutionWatch scoring model. DilutionWatch displays SEC filing and dilution indicators for SPRO, including shelf registrations, ATM offerings, warrant exercises, PIPE deals, and reverse split signals when detected in source data.

What SEC filings does DilutionWatch track for SPRO?

DilutionWatch tracks 25 SEC filing types for SPRO including S-3 shelf registrations, 424B prospectuses (ATM offerings), S-1 registration statements, 8-K material events, warrant exercise notices, convertible note agreements, and Form 4 insider transactions. Alerts are delivered via email within minutes of a filing appearing on EDGAR.

How does stock dilution affect SPRO shareholders?

Stock dilution occurs when a company issues new shares, reducing the ownership percentage of existing shareholders. For SPRO, common dilution events include at-the-market (ATM) stock offerings, shelf registration drawdowns, warrant exercises, and convertible note conversions. Each event increases the share count and can pressure the stock price lower.

Is DilutionWatch free for SPRO tracking?

DilutionWatch provides a free tier that shows DilutionScores and basic filing history for SPRO. Premium plans ($19.95/month Basic, $39.95/month Premium) unlock real-time email alerts, the full Pulse™ feed, advanced dilution forecasts, and access to all 10,000+ tracked tickers.

SPRO Dilution Risk Score: 26/100 (MEDIUM)

Score Breakdown

📋 Offering Ability

40

💰Cash Runway—

📊 Float Risk

25

⚠️ Warrant Exposure

40

🔄 Convertible Debt

40

Dilution Forecast

☀️

Clear

No significant dilution signals

model est. 0%

No significant dilution signals detected for SPRO.

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Market Data

Market Cap$163.86M

Shares Outstanding58.23M

Float46.52M

Cash$50.77M

Debt$2.47M

Short InterestN/A

Institutional Holdings

QoQ: ↑ 8.0% shares (2026Q1 vs prior)

51 institutional holders · 23.08M shares

#1 GSK plc 9.19M shares

#2 VANGUARD CAPITAL MANAGEMENT LLC 3.60M shares

#3 Pfizer Inc 2.36M shares

+ 17 more holders Sign up free to view →

Institutional holder totals are aggregated from ownership filings and may use a different share basis or reporting date than public float. They are not a reconciliation against tradeable float.

Short Interest

Short Interest1.51M

Days to Cover1.0

% of Float3.2%

FINRA data as of Jul 31, 2026

Insider Buy/Sell Ratio

Recent SEC Activity

xbrl XBRL CONVERTIBLE 2022-12-31

Full SEC filing analysis available with free account →

Recent News

No recent news

Factual SPRO Dilution Snapshot

Spero Therapeutics, Inc. (SPRO) has a DilutionScore of 26/100, rated Medium dilution risk. Score date: August 28, 2026.

Recent SEC activity tracked for SPRO: xbrl on 2022-12-31.

This automatically generated snapshot is assembled from stored DilutionWatch data fields and may contain data-source errors or omissions. It is not financial advice, not investment research, and not a recommendation. Do your own research and review the full disclaimer and terms of service.