Spero TherapeuticsSPRO -1.37%55 Net-Net Working Capital is $0.86 as of Mar. 2026. GuruFocus rates SPRO with a GF Score™ of 55/100 and a GF Value™ of $1.05 (Significantly Overvalued). The stock has 4 warning signs investors should review. Among 859 Biotechnology companies, Spero Therapeutics ranks better than 74.27% on this metric.
In calculating the Net-Net Working Capital (NNWC), Benjamin Graham assumed that a company's accounts receivable is only worth 75% its value, its inventory is only worth 50% of its value, but its liabilities have to be paid in full. In addition, Graham believed that preferred stock belongs on the liability side of the balance sheet, not as part of capital and surplus. This is a conservative way of estimating the company's value.
Spero Therapeutics's Net-Net Working Capital for the quarter that ended in Mar. 2026 was $0.86.
The industry rank for Spero Therapeutics's Net-Net Working Capital or its related term are showing as below:
SPRO's Price-to-Net-Net-Working-Capital is ranked better than 74.27% of 859
companies
in the Biotechnology industry
Industry Median: 5.48
vs SPRO: 2.51
Spero Therapeutics (NAS:SPRO) Net-Net Working Capital Explanation
One research study, covering the years 1970 through 1983 showed that portfolios picked at the beginning of each year, and held for one year, returned 29.4 percent, on average, over the 13-year period, compared to 11.5 percent for the S&P 500 Index. Other studies of Graham's strategy produced similar results.
Benjamin Graham looked for companies whose market values were less than two-thirds of their net-net value. They are collected under our Net-Net screener.
Spero Therapeutics Net-Net Working Capital Related Terms
Spero Therapeutics Net-Net Working Capital Historical Data
* Premium members only.
The historical data trend for Spero Therapeutics's Net-Net Working Capital 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.
SPRO vs VXRT, ADCT, GNLX: Net-Net Working Capital Comparison
For the Biotechnology subindustry, Spero Therapeutics's Price-to-Net-Net-Working-Capital, along with its competitors' market caps and Price-to-Net-Net-Working-Capital 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 Price-to-Net-Net-Working-Capital vs Biotechnology Industry
For the Biotechnology industry and Healthcare sector, Spero Therapeutics's Price-to-Net-Net-Working-Capital distribution charts can be found below:
* The bar in red indicates where Spero Therapeutics's Price-to-Net-Net-Working-Capital falls into.
* 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.
In calculating the Net-Net Working Capital (NNWC), Benjamin Graham assumed that a company's accounts receivable is only worth 75% its value, its inventory is only worth 50% of its value, but its liabilities have to be paid in full.
In addition, Graham believed that preferred stock belongs on the liability side of the balance sheet, not as part of capital and surplus. In "Security Analysis", preferred stock is dubbed "an imperfect creditorship position" that is best placed on the balance sheet alongside funded debt.
This is a conservative way of estimating the company's value.
What does a Net-Net Working Capital of $0.86 mean?
Spero Therapeutics (SPRO) has a Net-Net Working Capital of $0.86 as of Mar. 2026. Ben Graham defined net-net working capital as the per-share sum of cash, 75% of receivables and 50% of inventory less total liabilities. View historical data on Spero Therapeutics According to the industry distribution chart, Spero Therapeutics ranks #221 out of 859 companies in the Biotechnology industry, placing it in the top 25.7%.
Is Spero Therapeutics' Net-Net Working Capital too high?
Spero Therapeutics' current Net-Net Working Capital is $0.86. The Biotechnology industry median Net-Net Working Capital is 5.48. Spero Therapeutics' value of $0.86 is 84.3% below this industry median. Based on the distribution chart, Spero Therapeutics ranks #221 out of 859 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' Net-Net Working Capital compare to VXRT and ADCT?
According to the Biotechnology industry distribution chart, Spero Therapeutics ranks #221 out of 859 companies for Net-Net Working Capital. This puts Spero Therapeutics in the upper half of its industry. The industry median Net-Net Working Capital is 5.48. Spero Therapeutics' value of $0.86 is 84.3% 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 Net-Net Working Capital for a Biotechnology company?
The median Net-Net Working Capital among Biotechnology companies is 5.48, based on 859 companies in the industry. Companies in the top quartile (top 25%) have a Net-Net Working Capital significantly above this median, while those in the bottom quartile fall well below. However, Net-Net Working Capital should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Spero Therapeutics's current Net-Net Working Capital of $0.86 is 84.3% 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 Net-Net Working Capital mean?
A high Net-Net Working Capital can signal that a stock is expensive relative to its fundamentals. Ben Graham defined net-net working capital as the per-share sum of cash, 75% of receivables and 50% of inventory less total liabilities. View historical data on Spero Therapeutics For the Biotechnology industry, the median Net-Net Working Capital is 5.48 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Spero Therapeutics's current Net-Net Working Capital is $0.86. 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 $1.05, compared to a current price of $2.16 — trading 105.7% above its estimated fair value. The current Net-Net Working Capital is $0.86 and 84.3% below the Biotechnology industry median of 5.48. 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 Net-Net Working Capital calculated?
Net-Net Working Capital is calculated from a company's financial statements. For Spero Therapeutics (SPRO), the current Net-Net Working Capital is $0.86 as of Mar. 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 $2.16 is trading 105.7% above its estimated GF Value™ of $1.05.
GuruFocus considers Spero Therapeutics to be Significantly Overvalued.
Key valuation signals for SPRO:
Net-Net Working Capital: $0.86
GF Value™: $1.05 vs. price of $2.16 (105.7% above fair value)
Industry Position: 84.3% below the Biotechnology median (#221 of 859)
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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