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Sutro BiopharmaSTRO -4.16%45 Piotroski F-Score is 3 as of Aug. 16, 2026, which is at its 10-year median of 3.00. GuruFocus rates STRO with a GF Score™ of 45/100 and a GF Value™ of $5.50 (Significantly Overvalued). The stock has 4 warning signs investors should review. Among 1,329 Biotechnology companies, Sutro Biopharma ranks better than 54.63% on this metric.
Warning Sign:
Piotroski F-Score of 3 is low, which usually implies poor business operation.
The zones of discrimination were as such:
Good or high score = 7, 8, 9
Bad or low score = 0, 1, 2, 3
Sutro Biopharma has an F-score of 3. It is a bad or low score, which usually implies poor business operation.
The historical rank and industry rank for Sutro Biopharma's Piotroski F-Score or its related term are showing as below:
STRO'
s Piotroski F-Score Range Over the Past 10 Years
Min: 1 Med: 3 Max: 5
Current: 3
During the past 10 years, the highest Piotroski F-Score of Sutro Biopharma was 5. The lowest was 1. And the median was 3.
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.
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.
Sutro Biopharma Piotroski F-Score Related Terms
Sutro Biopharma Piotroski F-Score Historical Data
* Premium members only.
The historical data trend for Sutro Biopharma'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.
STRO vs AVIR, IPSC, CCCC: Piotroski F-Score Comparison
For the Biotechnology subindustry, Sutro Biopharma'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.
Sutro Biopharma Piotroski F-Score vs Biotechnology Industry
For the Biotechnology industry and Healthcare sector, Sutro Biopharma's Piotroski F-Score distribution charts can be found below:
* The bar in red indicates where Sutro Biopharma's Piotroski F-Score 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.
*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.
Sutro Biopharma's current Net Income (TTM) was -180.64.
==> Negative ==> Score 0.
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.
Sutro Biopharma's return on assets of this year was -0.68851747. Sutro Biopharma's return on assets of last year was -0.42674571.
==> Last year is higher ==> Score 0.
Question 4. Quality of Earnings (Accrual)
Compare Cash flow return on assets (2) to return on assets (1)
Sutro Biopharma's gearing of this year was 0.01904752. Sutro Biopharma's gearing of last year was 0.03016946.
==> 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
Sutro Biopharma's current ratio of this year was 3.32048471. Sutro Biopharma's current ratio of last year was 3.11976403.
==> 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.
Sutro Biopharma's number of shares in issue this year was 16.572. Sutro Biopharma's number of shares in issue last year was 8.512.
==> 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.
Sutro Biopharma's gross margin of this year was 1. Sutro Biopharma'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
Sutro Biopharma's asset turnover of this year was 0.17419908. Sutro Biopharma's asset turnover of last year was 0.21362743.
==> Last year's asset turnover is higher ==> Score 0.
Evaluation
Piotroski F-Score
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Good or high score = 7, 8, 9
Bad or low score = 0, 1, 2, 3
Sutro Biopharma has an F-score of 3. It is a bad or low score, which usually implies poor business operation.
Sutro Biopharma (STRO) has a Piotroski F-Score of 3 as of Aug. 16, 2026. The Piotroski F-score grades a company's business operating strength from 0-9. View historical data on Sutro Biopharma and its competitors. This is near median its historical median of 3.00. Over the past decade, Sutro Biopharma's Piotroski F-Score has ranged from 1.00 to 5.00. According to the industry distribution chart, Sutro Biopharma ranks #603 out of 1329 companies in the Biotechnology industry, placing it in the top 45.4%.
Is Sutro Biopharma's Piotroski F-Score too high?
Sutro Biopharma's current Piotroski F-Score of 3 is near 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 5.00. The Biotechnology industry median Piotroski F-Score is 3.00. Sutro Biopharma's value of 3 is 0% at this industry median. Based on the distribution chart, Sutro Biopharma ranks #603 out of 1329 companies in the Biotechnology industry, which is above the industry midpoint. Overall, Sutro Biopharma has a GF Score™ of 45/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Sutro Biopharma's Piotroski F-Score compare to AVIR and IPSC?
According to the Biotechnology industry distribution chart, Sutro Biopharma ranks #603 out of 1329 companies for Piotroski F-Score. This puts Sutro Biopharma in the upper half of its industry. The industry median Piotroski F-Score is 3.00. Sutro Biopharma's value of 3 is 0% at this benchmark. Historically, Sutro Biopharma's own Piotroski F-Score has ranged from 1.00 to 5.00 over the past decade. While the company's 10-year median is 3.00 vs. the industry median of 3.00, Sutro Biopharma has consistently been at 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 1,329 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. Sutro Biopharma's current Piotroski F-Score of 3 is 0% at 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 Sutro Biopharma 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. Sutro Biopharma's current Piotroski F-Score is 3, which is near 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 Sutro Biopharma stock overvalued right now?
Based on GuruFocus' analysis, Sutro Biopharma (STRO) is currently considered Significantly Overvalued. The stock's GF Value™ is $5.50, compared to a current price of $20.46 — trading 272% above its estimated fair value. The current Piotroski F-Score is 3, which is near median its 10-year median of 3.00 and 0% at the Biotechnology industry median of 3.00. Sutro Biopharma's overall GF Score™ is 45/100 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 Sutro Biopharma (STRO), the current Piotroski F-Score is 3 as of Aug. 16, 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 Sutro Biopharma (STRO) Overvalued in 2026?
Based on GuruFocus' analysis, Sutro Biopharma stock appears to be overvalued.
The current stock price of $20.46 is trading 272% above its estimated GF Value™ of $5.50.
GuruFocus considers Sutro Biopharma to be Significantly Overvalued.
Key valuation signals for STRO:
Piotroski F-Score: 3 (near median its 10-year median of 3.00)
GF Value™: $5.50 vs. price of $20.46 (272% above fair value)
Industry Position: 0% at the Biotechnology median (#603 of 1329)
No single metric tells the full story. See the STRO stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Sutro Biopharma Inc is a clinical-stage drug discovery, development, and manufacturing company. The company manufactures next-generation protein therapeutics for cancer and autoimmune disorders through its proprietary integrated cell-free protein synthesis platform, XpressCF. Products offered by the company include STRO-001 for patients with multiple myeloma and lymphoma and STRO-002 for the treatment of ovarian and endometrial cancers. Company's wholly-owned product candidate is STRO-004, a single homogeneous ADC directed against tissue factor which are developing for the treatment of solid tumors. The company also pipeline contains STRO-006, STRO-00X, STRO-00Y, STRO-003, VAX24, VAX31, and Others.
45GF Score
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