SPRO (Spero Therapeutics) Piotroski F-Score: 6 (As of Jun. 26, 2026) — 100% Above Median


SPRO Spero Therapeutics Inc SPRO
55 GF Score
Price $2.02
GF Value $1.06
Valuation Significantly Overvalued
! 4 Warning Signs
View Full Analysis

What is Spero Therapeutics Piotroski F-Score?

Spero Therapeutics SPRO -4.04% 55 Piotroski F-Score is 6 as of Jun. 26, 2026, which is 100% above its 10-year median of 3.00. GuruFocus rates SPRO with a GF Score™ of 55/100 and a GF Value™ of $1.06 (Significantly Overvalued). The stock has 4 warning signs investors should review. Among 1,342 Biotechnology companies, Spero Therapeutics ranks better than 92.03% on this metric.

The zones of discrimination were as such:

Good or high score = 7, 8, 9
Bad or low score = 0, 1, 2, 3

Spero Therapeutics has an F-score of 6 indicating the company's financial situation is typical for a stable company.

The historical rank and industry rank for Spero Therapeutics's Piotroski F-Score or its related term are showing as below:

SPRO' s Piotroski F-Score Range Over the Past 10 Years
Min: 1   Med: 3   Max: 6
Current: 6

During the past 11 years, the highest Piotroski F-Score of Spero Therapeutics was 6. The lowest was 1. And the median was 3.

Spero Therapeutics  (NAS:SPRO) Piotroski F-Score Explanation

The developer of the system is Joseph D. Piotroski is relatively unknown accounting professor who shuns publicity and rarely gives interviews.

He graduated from the University of Illinois with a B.S. in accounting in 1989, received an M.B.A. from Indiana University in 1994. Five years later, in 1999, after earning a Ph.D. in accounting from the University of Michigan, he became an associate professor of accounting at the University of Chicago.

In 2000, he wrote a research paper called "Value Investing: The Use of Historical Financial Statement Information to Separate Winners from Losers" (pdf).

He wanted to see if he can develop a system (using a simple nine-point scoring system) that can increase the returns of a strategy of investing in low price to book (referred to in the paper as high book to market) value companies.

What he found was something that exceeded his most optimistic expectations.

Buying only those companies that scored highest (8 or 9) on his nine-point scale, or F-Score as he called it, over the 20 year period from 1976 to 1996 led to an average out-performance over the market of 13.4%.

Even more impressive were the results of a strategy of investing in the highest F-Score companies (8 or 9) and shorting companies with the lowest F-Score (0 or 1).

Over the same period from 1976 to 1996 (20 years) this strategy led to an average yearly return of 23%, substantially outperforming the average S&P 500 index return of 15.83% over the same period.


Spero Therapeutics Piotroski F-Score Related Terms


Spero Therapeutics Piotroski F-Score Historical Data

* Premium members only.

The historical data trend for Spero Therapeutics's Piotroski F-Score 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.

Spero Therapeutics Piotroski F-Score Chart

Spero Therapeutics Annual Data
Trend Dec16 Dec17 Dec18 Dec19 Dec20 Dec21 Dec22 Dec23 Dec24 Dec25
Piotroski F-Score
Get a 7-Day Free Trial Premium Member Only Premium Member Only 4.00 3.00 4.00 2.00 5.00

Spero Therapeutics Quarterly Data
Jun21 Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25 Mar26
Piotroski F-Score Get a 7-Day Free Trial Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only 2.00 3.00 3.00 5.00 6.00

SPRO vs ORMP, PLYX, HRTX: Piotroski F-Score Comparison

For the Biotechnology subindustry, Spero Therapeutics's Piotroski F-Score, along with its competitors' market caps and Piotroski F-Score 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 Piotroski F-Score vs Biotechnology Industry

For the Biotechnology industry and Healthcare sector, Spero Therapeutics's Piotroski F-Score distribution charts can be found below:

* The bar in red indicates where Spero Therapeutics's Piotroski F-Score falls into.


SPRO
55GF Score
Spero Therapeutics Inc SPRO
Piotroski F-Score is just one metric. See GF Score™, valuation, warning signs, and more.
View Full Analysis

How is the Piotroski F-Score calculated?

* 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.

This Year (Mar26) TTM:Last Year (Mar25) TTM:
Net Income was -1.7 + -7.382 + 31.52 + -7.203 = $15.24 Mil.
Cash Flow from Operations was -17.693 + 17.422 + -8.351 + 15.864 = $7.24 Mil.
Revenue was 11.802 + 3.048 + 39.658 + 0.258 = $54.77 Mil.
Gross Profit was 11.802 + 3.048 + 39.658 + 0.258 = $54.77 Mil.
Average Total Assets from the begining of this year (Mar25)
to the end of this year (Mar26) was
(77.709 + 62.119 + 54.17 + 68.919 + 59.021) / 5 = $64.3876 Mil.
Total Assets at the begining of this year (Mar25) was $77.71 Mil.
Long-Term Debt & Capital Lease Obligation was $0.51 Mil.
Total Current Assets was $57.61 Mil.
Total Current Liabilities was $5.49 Mil.
Net Income was -17.862 + -17.147 + -20.888 + -13.866 = $-69.76 Mil.

Revenue was 6.017 + 7.819 + 9.356 + 5.111 = $28.30 Mil.
Gross Profit was 6.017 + 7.819 + 9.356 + 5.111 = $28.30 Mil.
Average Total Assets from the begining of last year (Mar24)
to the end of last year (Mar25) was
(167.703 + 149.881 + 135.161 + 110.543 + 77.709) / 5 = $128.1994 Mil.
Total Assets at the begining of last year (Mar24) was $167.70 Mil.
Long-Term Debt & Capital Lease Obligation was $2.17 Mil.
Total Current Assets was $74.71 Mil.
Total Current Liabilities was $29.16 Mil.

*Note: If the latest quarterly/semi-annual/annual total assets data is 0, then we will use previous quarterly/semi-annual/annual data for all the items in the balance sheet.

Profitability

Question 1. Return on Assets (ROA)

Net income before extraordinary items for the year divided by Total Assets at the beginning of the year.

Score 1 if positive, 0 if negative.

Spero Therapeutics's current Net Income (TTM) was 15.24. ==> Positive ==> Score 1.

Question 2. Cash Flow Return on Assets (CFROA)

Net cash flow from operating activities (operating cash flow) divided by Total Assets at the beginning of the year.

Score 1 if positive, 0 if negative.

Spero Therapeutics's current Cash Flow from Operations (TTM) was 7.24. ==> Positive ==> Score 1.

Question 3. Change in Return on Assets

Compare this year's return on assets (1) to last year's return on assets.

Score 1 if it's higher, 0 if it's lower.

ROA (This Year)=Net Income/Total Assets (Mar25)
=15.235/77.709
=0.19605194

ROA (Last Year)=Net Income/Total Assets (Mar24)
=-69.763/167.703
=-0.41599137

Spero Therapeutics's return on assets of this year was 0.19605194. Spero Therapeutics's return on assets of last year was -0.41599137. ==> This year is higher. ==> Score 1.

Question 4. Quality of Earnings (Accrual)

Compare Cash flow return on assets (2) to return on assets (1)

Score 1 if CFROA > ROA, 0 if CFROA <= ROA.

Spero Therapeutics's current Net Income (TTM) was 15.24. Spero Therapeutics's current Cash Flow from Operations (TTM) was 7.24. ==> 7.24 <= 15.24 ==> CFROA <= ROA ==> Score 0.

Funding

Question 5. Change in Gearing or Leverage

Compare this year's gearing (long-term debt divided by average total assets) to last year's gearing.

Score 0 if this year's gearing is higher, 1 otherwise.

Gearing (This Year: Mar26)=Long-Term Debt & Capital Lease Obligation/Average Total Assets from Mar25 to Mar26
=0.507/64.3876
=0.00787419

Gearing (Last Year: Mar25)=Long-Term Debt & Capital Lease Obligation/Average Total Assets from Mar24 to Mar25
=2.165/128.1994
=0.01688775

Spero Therapeutics's gearing of this year was 0.00787419. Spero Therapeutics's gearing of last year was 0.01688775. ==> This year is lower or equal to last year. ==> Score 1.

Question 6. Change in Working Capital (Liquidity)

Compare this year's current ratio (current assets divided by current liabilities) to last year's current ratio.

Score 1 if this year's current ratio is higher, 0 if it's lower

Current Ratio (This Year: Mar26)=Total Current Assets/Total Current Liabilities
=57.612/5.489
=10.49590089

Current Ratio (Last Year: Mar25)=Total Current Assets/Total Current Liabilities
=74.714/29.155
=2.56264792

Spero Therapeutics's current ratio of this year was 10.49590089. Spero Therapeutics's current ratio of last year was 2.56264792. ==> This year's current ratio is higher. ==> Score 1.

Question 7. Change in Shares in Issue

Compare the number of shares in issue this year, to the number in issue last year.

Score 0 if there is larger number of shares in issue this year, 1 otherwise.

Spero Therapeutics's number of shares in issue this year was 57.282. Spero Therapeutics's number of shares in issue last year was 55.376. ==> There is larger number of shares in issue this year. ==> Score 0.

Efficiency

Question 8. Change in Gross Margin

Compare this year's gross margin (Gross Profit divided by sales) to last year's.

Score 1 if this year's gross margin is higher, 0 if it's lower.

Gross Margin (This Year: TTM)=Gross Profit/Revenue
=54.766/54.766
=1

Gross Margin (Last Year: TTM)=Gross Profit/Revenue
=28.303/28.303
=1

Spero Therapeutics's gross margin of this year was 1. Spero Therapeutics's gross margin of last year was 1. ==> Last year's gross margin is higher ==> Score 0.

Question 9. Change in asset turnover

Compare this year's asset turnover (total sales for the year divided by total assets at the beginning of the year) to last year's asset turnover ratio.

Score 1 if this year's asset turnover ratio is higher, 0 if it's lower

Asset Turnover (This Year)=Revenue/Total Assets at the Beginning of This Year (Mar25)
=54.766/77.709
=0.70475749

Asset Turnover (Last Year)=Revenue/Total Assets at the Beginning of Last Year (Mar24)
=28.303/167.703
=0.1687686

Spero Therapeutics's asset turnover of this year was 0.70475749. Spero Therapeutics's asset turnover of last year was 0.1687686. ==> This year's asset turnover is higher. ==> Score 1.

Evaluation

Piotroski F-Score= Que. 1+ Que. 2+ Que. 3+Que. 4+Que. 5+Que. 6+Que. 7+Que. 8+Que. 9
=1+1+1+0+1+1+0+0+1
=6

Good or high score = 7, 8, 9
Bad or low score = 0, 1, 2, 3

Spero Therapeutics has an F-score of 6 indicating the company's financial situation is typical for a stable company.

Frequently Asked Questions Learn more about Piotroski F-Score →
What does a Piotroski F-Score of 6 mean?
Spero Therapeutics (SPRO) has a Piotroski F-Score of 6 as of Jun. 26, 2026. The Piotroski F-score grades a company's business operating strength from 0-9. View historical data on Spero Therapeutics and its competitors. This is 100% above median its historical median of 3.00. Over the past decade, Spero Therapeutics' Piotroski F-Score has ranged from 1.00 to 6.00. According to the industry distribution chart, Spero Therapeutics ranks #107 out of 1342 companies in the Biotechnology industry, placing it in the top 8%.
Is Spero Therapeutics' Piotroski F-Score too high?
Spero Therapeutics' current Piotroski F-Score of 6 is 100% above median its 10-year median of 3.00. Over the past 10 years, this metric has ranged from a low of 1.00 to a high of 6.00. The Biotechnology industry median Piotroski F-Score is 3.00. Spero Therapeutics' value of 6 is 100% above this industry median. Based on the distribution chart, Spero Therapeutics ranks #107 out of 1342 companies in the Biotechnology industry, which is in the top quartile — a strong position relative to peers. 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' Piotroski F-Score compare to ORMP and PLYX?
According to the Biotechnology industry distribution chart, Spero Therapeutics ranks #107 out of 1342 companies for Piotroski F-Score. This places Spero Therapeutics in the top 8% of its industry — outperforming the majority of peers. The industry median Piotroski F-Score is 3.00. Spero Therapeutics' value of 6 is 100% above this benchmark. Historically, Spero Therapeutics' own Piotroski F-Score has ranged from 1.00 to 6.00 over the past decade. While the company's 10-year median is 3.00 vs. the industry median of 3.00, Spero Therapeutics has consistently been above the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Piotroski F-Score for a Biotechnology company?
The median Piotroski F-Score among Biotechnology companies is 3.00, based on 1,342 companies in the industry. Companies in the top quartile (top 25%) have a Piotroski F-Score significantly above this median, while those in the bottom quartile fall well below. However, Piotroski F-Score should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Spero Therapeutics's current Piotroski F-Score of 6 is 100% above 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 Piotroski F-Score mean?
A high Piotroski F-Score can signal that a stock is expensive relative to its fundamentals. The Piotroski F-score grades a company's business operating strength from 0-9. View historical data on Spero Therapeutics and its competitors. For the Biotechnology industry, the median Piotroski F-Score is 3.00 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Spero Therapeutics's current Piotroski F-Score is 6, which is 100% above median its own 10-year median of 3.00. 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 Piotroski F-Score is 6, which is 100% above median its 10-year median of 3.00 and 100% above the Biotechnology industry median of 3.00. 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 Piotroski F-Score calculated?
Piotroski F-Score is calculated from a company's financial statements. For Spero Therapeutics (SPRO), the current Piotroski F-Score is 6 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:

  • Piotroski F-Score: 6 (100% above median its 10-year median of 3.00)
  • GF Value™: $1.06 vs. price of $2.02 (90.6% above fair value)
  • GF Score™: 55/100 with 4 warning signs
  • Industry Position: 100% above the Biotechnology median (#107 of 1342)

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 Business Description

Other Exchanges 2HA:Germany
Address 675 Massachusetts Avenue, 14th Floor, Cambridge, MA, USA, 02139
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

Get the complete analysis for SPRO

Piotroski F-Score is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.

$2.02
Price
$1.06
GF Value