Market cap is the total market value to buy the whole company. It is equal to the share price times the number of Shares Outstanding (EOP). Spero Therapeutics's share price for the quarter that ended in Mar. 2026 was $2.34. Spero Therapeutics's Shares Outstanding (EOP) for the quarter that ended in Mar. 2026 was 57.89 Mil. Therefore, Spero Therapeutics's market cap for the quarter that ended in Mar. 2026 was $135.46 Mil.
Spero Therapeutics's quarterly market cap
increased
from Sep. 2025 ($105.87 Mil) to Dec. 2025 ($131.45 Mil) and
increased
from Dec. 2025 ($131.45 Mil) to Mar. 2026 ($135.46 Mil).
Spero Therapeutics's annual market cap
declined
from Dec. 2023 ($77.91 Mil) to Dec. 2024 ($56.23 Mil) but then
increased
from Dec. 2024 ($56.23 Mil) to Dec. 2025 ($131.45 Mil).
Enterprise Value is the theoretical takeover price. It is more comprehensive than market capitalization (market cap), which only includes common equity. Enterprise Value is calculated as the market cap plus debt and minority interest and preferred shares, minus total cash and cash equivalents. Spero Therapeutics's Enterprise Value for Today is $63.30 Mil.
Spero Therapeutics (NAS:SPRO) Market Cap Explanation
Market cap is not the real price you pay for a company. If you buy the company and become its owner, you become the owner of the cash the company has, and you also assume the companys debt. The real price you pay is the Enterprise Value.
Warren Buffett uses the ratio of total market cap of all public traded companies over GDP to measure if the market is expensive. As of April 2012, the US total market cap is about $14.7 trillion, while the US GDP is about $15 trillion. The market was modestly overvalued.
Spero Therapeutics Market Cap Related Terms
Spero Therapeutics Market Cap Historical Data
* Premium members only.
The historical data trend for Spero Therapeutics's Market Cap can be seen below:
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
For the Biotechnology subindustry, Spero Therapeutics's Market Cap, along with its competitors' market caps and Market Cap data, can be viewed below:
* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.
Spero Therapeutics Market Cap vs Biotechnology Industry
For the Biotechnology industry and Healthcare sector, Spero Therapeutics's Market Cap distribution charts can be found below:
* The bar in red indicates where Spero Therapeutics's Market Cap falls into.
Market cap is the short version of market capitalization. It is the total market value to buy the whole company. It is equal to the share price times the number of shares outstanding.
Spero Therapeutics's Market Cap for the fiscal year that ended in Dec. 2025 is calculated as
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
Spero Therapeutics (SPRO) has a Market Cap of $116.96 Mil as of Jun. 26, 2026. Market cap equals the total value of a company's shares: price times shares outstanding. View historical data on Spero Therapeutics and its competitors. According to the industry distribution chart, Spero Therapeutics ranks #706 out of 1431 companies in the Biotechnology industry, placing it in the top 49.3%.
Is Spero Therapeutics' Market Cap too high?
Spero Therapeutics' current Market Cap is $116.96 Mil. The Biotechnology industry median Market Cap is 117.63. Spero Therapeutics' value of $116.96 Mil is 0.6% below this industry median. Based on the distribution chart, Spero Therapeutics ranks #706 out of 1431 companies in the Biotechnology industry, which is above the industry midpoint. Overall, Spero Therapeutics has a GF Score™ of 55/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Spero Therapeutics' Market Cap compare to ORMP and PLYX?
According to the Biotechnology industry distribution chart, Spero Therapeutics ranks #706 out of 1431 companies for Market Cap. This puts Spero Therapeutics in the upper half of its industry. The industry median Market Cap is 117.63. Spero Therapeutics' value of $116.96 Mil is 0.6% below this benchmark. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Market Cap for a Biotechnology company?
The median Market Cap among Biotechnology companies is 117.63, based on 1,431 companies in the industry. Companies in the top quartile (top 25%) have a Market Cap significantly above this median, while those in the bottom quartile fall well below. However, Market Cap should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Spero Therapeutics's current Market Cap of $116.96 Mil is 0.6% below the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Market Cap mean?
A high Market Cap can signal that a stock is expensive relative to its fundamentals. Market cap equals the total value of a company's shares: price times shares outstanding. View historical data on Spero Therapeutics and its competitors. For the Biotechnology industry, the median Market Cap is 117.63 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Spero Therapeutics's current Market Cap is $116.96 Mil. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Spero Therapeutics stock overvalued right now?
Based on GuruFocus' analysis, Spero Therapeutics (SPRO) is currently considered Significantly Overvalued. The stock's GF Value™ is $1.06, compared to a current price of $2.02 — trading 90.6% above its estimated fair value. The current Market Cap is $116.96 Mil and 0.6% below the Biotechnology industry median of 117.63. Spero Therapeutics' overall GF Score™ is 55/100 with 4 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Market Cap calculated?
Market Cap is calculated from a company's financial statements. For Spero Therapeutics (SPRO), the current Market Cap is $116.96 Mil as of Jun. 26, 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.
Is Spero Therapeutics (SPRO) Overvalued in 2026?
Based on GuruFocus' analysis, Spero Therapeutics stock appears to be overvalued.
The current stock price of $2.02 is trading 90.6% above its estimated GF Value™ of $1.06.
GuruFocus considers Spero Therapeutics to be Significantly Overvalued.
Key valuation signals for SPRO:
Market Cap: $116.96 Mil
GF Value™: $1.06 vs. price of $2.02 (90.6% above fair value)
Industry Position: 0.6% below the Biotechnology median (#706 of 1431)
No single metric tells the full story. See the SPRO stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Spero Therapeutics Inc is a clinical-stage biopharmaceutical firm. It focuses on identifying, developing, and commercializing novel treatments for MDR (Multi-drug-resistant) bacterial infections and rare diseases. The company's product candidate, tebipenem pivoxil hydrobromide or tebipenem HBr, is designed to be an oral carbapenem-class antibiotic for use in adults to treat MDR Gram-negative infections. It is also developing SPR720, a novel oral antibiotic designed for the treatment of a rare, orphan disease caused by pulmonary non-tuberculous mycobacterial infections, or NTM disease. It is also focused on SPR206, a next-generation polymyxin investigational product candidate being developed as an IV-administered medicine to treat MDR Gram-negative infections in the hospital.
55GF Score
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