Spero Therapeutics (SPRO) Shares Outstanding (Diluted) (2021 - 2026)
Spero Therapeutics (SPRO) posted Shares Outstanding (Diluted) of 57.97 million for Q2 2026, up 3.5% from 56.03 million a year earlier and up 1.2% from the prior quarter.
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Analysis
Spero Therapeutics (SPRO) Shares Outstanding (Diluted) (2021 - 2026) Analysis & Trends
For FY2025, Spero Therapeutics' Shares Outstanding (Diluted) came in at 59.04 million, up 9.3% from FY2024.
- Annual Shares Outstanding (Diluted) has increased for four consecutive years, with a four-year compound annual growth rate of 17.6% (FY2021 to FY2025).
- In prior years, Spero Therapeutics' Shares Outstanding (Diluted) was 54.04 million in FY2024 (+2.0%), 52.99 million in FY2023 (+41.0%), 37.59 million in FY2022 (+21.7%) and 30.9 million in FY2021.
- Quarterly Shares Outstanding (Diluted) has run from a low of 30.9 million in Q4 2021 to a high of 59.04 million in Q4 2025 over five years.
- On a year-over-year basis, Shares Outstanding (Diluted) has increased in each of the last 17 quarters, with growth averaging 4.0% over the last eight quarters.
- Across the past five years, year-over-year growth in Shares Outstanding (Diluted) ran from 1.9% in Q1 2024 to 61.1% in Q1 2023.
- According to Business Quant data, Shares Outstanding (Diluted) for the three prior quarters was 57.28 million (Q1 2026), 59.04 million (Q4 2025) and 56.28 million (Q3 2025).
Peer Set
Peer Comparison
| # | Company | Market Cap | Enterprise Value | Gross Profit (Qtr) | Shares Outstanding (Dil.) (Qtr) |
|---|---|---|---|---|---|
| 1 | Eli Lilly | 1,136.97 Bn | 1,105.55 Bn | 19.71 Bn | 893.70 Mn |
| 2 | Johnson & Johnson | 619.72 Bn | 538.25 Bn | 17.26 Bn | 2.44 Bn |
| 3 | AbbVie | 503.40 Bn | 476.52 Bn | 12.70 Bn | 1.77 Bn |
| 4 | Merck | 370.15 Bn | 324.53 Bn | 12.21 Bn | 2.47 Bn |
| 5 | Novartis Ag | 298.64 Bn | 262.63 Bn | 11.24 Bn | 1.96 Bn |
| 6 | Astrazeneca | 261.07 Bn | 234.76 Bn | 12.86 Bn | 1.56 Bn |
| 7 | Amgen | 237.00 Bn | 192.40 Bn | 7.24 Bn | 544.00 Mn |
| 8 | Gilead Sciences | 191.24 Bn | 165.43 Bn | 6.22 Bn | 1.24 Bn |
| 9 | Pfizer | 170.31 Bn | 116.96 Bn | 10.94 Bn | 5.70 Bn |
| 10 | Spero Therapeutics | 68.40 Mn | -127.38 Mn | - | 57.97 Mn |
Historic Data
Download Data
Historic Data
| Date | Value |
|---|---|
| Jun 30, 2026 | 57.97 Mn |
| Mar 31, 2026 | 57.28 Mn |
| Dec 31, 2025 | 59.04 Mn |
| Sep 30, 2025 | 56.28 Mn |
| Jun 30, 2025 | 56.03 Mn |
| Mar 31, 2025 | 55.38 Mn |
| Dec 31, 2024 | 54.04 Mn |
| Sep 30, 2024 | 54.12 Mn |
| Jun 30, 2024 | 53.96 Mn |
| Mar 31, 2024 | 53.52 Mn |
| Dec 31, 2023 | 52.99 Mn |
| Sep 30, 2023 | 52.71 Mn |
| Jun 30, 2023 | 52.57 Mn |
| Mar 31, 2023 | 52.53 Mn |
| Dec 31, 2022 | 37.59 Mn |
| Sep 30, 2022 | 35.88 Mn |
| Jun 30, 2022 | 32.98 Mn |
| Mar 31, 2022 | 32.61 Mn |
| Dec 31, 2021 | 30.90 Mn |
| Sep 30, 2021 | 32.13 Mn |
API Access
Spero Therapeutics Shares Outstanding (Diluted) API
Pull this series into your own models, spreadsheets and apps with the Business Quant
Historical Metrics API. The request below matches the chart above — change the
frequency, period or values and it follows. Swap YOUR_API_KEY for your own key.
https://data.businessquant.com/historic?slug=shares-outstanding-diluted&ticker=SPRO&period=max&api_key=YOUR_API_KEYimport requests
url = "https://data.businessquant.com/historic"
params = {"slug": "shares-outstanding-diluted", "ticker": "SPRO", "period": "max", "api_key": "YOUR_API_KEY"}
data = requests.get(url, params=params).json()const res = await fetch("https://data.businessquant.com/historic?slug=shares-outstanding-diluted&ticker=SPRO&period=max&api_key=YOUR_API_KEY");
const data = await res.json();