NephrosNEPH +1.52%63 Piotroski F-Score is 3 as of Jun. 26, 2026, which is 25% below its 10-year median of 4.00. GuruFocus rates NEPH with a GF Score™ of 63/100 and a GF Value™ of $2.87 (Modestly Overvalued). The stock has 5 warning signs investors should review. Among 805 Medical Devices & Instruments companies, Nephros ranks worse than 77.02% 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
Nephros 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 Nephros's Piotroski F-Score or its related term are showing as below:
NEPH'
s Piotroski F-Score Range Over the Past 10 Years
Min: 2 Med: 4 Max: 8
Current: 3
During the past 13 years, the highest Piotroski F-Score of Nephros was 8. The lowest was 2. And the median was 4.
Nephros (NAS:NEPH) 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.
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.
Nephros Piotroski F-Score Related Terms
Nephros Piotroski F-Score Historical Data
* Premium members only.
The historical data trend for Nephros'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.
NEPH vs MLSS, HBIO, FEMY: Piotroski F-Score Comparison
For the Medical Instruments & Supplies subindustry, Nephros'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.
Nephros Piotroski F-Score vs Medical Devices & Instruments Industry
For the Medical Devices & Instruments industry and Healthcare sector, Nephros's Piotroski F-Score distribution charts can be found below:
* The bar in red indicates where Nephros'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.
Nephros's current Net Income (TTM) was 0.78.
==> 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.
Nephros's gearing of this year was 0.04373831. Nephros's gearing of last year was 0.08668814.
==> 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
Nephros's current ratio of this year was 4.54926791. Nephros's current ratio of last year was 5.92358366.
==> Last year's current ratio is higher ==> Score 0.
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.
Nephros's number of shares in issue this year was 10.991. Nephros's number of shares in issue last year was 10.616.
==> 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.
Nephros's gross margin of this year was 0.59945618. Nephros's gross margin of last year was 0.62447638.
==> 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
Nephros's asset turnover of this year was 1.62370521. Nephros's asset turnover of last year was 1.35923266.
==> This year's asset turnover is higher. ==> Score 1.
Evaluation
Piotroski F-Score
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Good or high score = 7, 8, 9
Bad or low score = 0, 1, 2, 3
Nephros has an F-score of 3. It is a bad or low score, which usually implies poor business operation.
Nephros (NEPH) has a Piotroski F-Score of 3 as of Jun. 26, 2026. The Piotroski F-score grades a company's business operating strength from 0-9. View historical data on Nephros and its competitors. This is 25% below median its historical median of 4.00. Over the past decade, Nephros' Piotroski F-Score has ranged from 2.00 to 8.00. According to the industry distribution chart, Nephros ranks #620 out of 805 companies in the Medical Devices & Instruments industry, placing it in the top 77%.
Is Nephros' Piotroski F-Score too high?
Nephros' current Piotroski F-Score of 3 is 25% below median its 10-year median of 4.00. Over the past 10 years, this metric has ranged from a low of 2.00 to a high of 8.00. The Medical Devices & Instruments industry median Piotroski F-Score is 5.00. Nephros' value of 3 is 40% below this industry median. Based on the distribution chart, Nephros ranks #620 out of 805 companies in the Medical Devices & Instruments industry, which is in the bottom quartile relative to peers. Overall, Nephros has a GF Score™ of 63/100 and is considered Modestly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Nephros' Piotroski F-Score compare to MLSS and HBIO?
According to the Medical Devices & Instruments industry distribution chart, Nephros ranks #620 out of 805 companies for Piotroski F-Score. This places Nephros in the lower half of its industry. The industry median Piotroski F-Score is 5.00. Nephros' value of 3 is 40% below this benchmark. Historically, Nephros' own Piotroski F-Score has ranged from 2.00 to 8.00 over the past decade. While the company's 10-year median is 4.00 vs. the industry median of 5.00, Nephros has consistently been below 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 Medical Devices & Instruments company?
The median Piotroski F-Score among Medical Devices & Instruments companies is 5.00, based on 805 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. Nephros's current Piotroski F-Score of 3 is 40% 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 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 Nephros and its competitors. For the Medical Devices & Instruments industry, the median Piotroski F-Score is 5.00 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Nephros's current Piotroski F-Score is 3, which is 25% below median its own 10-year median of 4.00. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Nephros stock overvalued right now?
Based on GuruFocus' analysis, Nephros (NEPH) is currently considered Modestly Overvalued. The stock's GF Value™ is $2.87, compared to a current price of $3.35 — trading 16.7% above its estimated fair value. The current Piotroski F-Score is 3, which is 25% below median its 10-year median of 4.00 and 40% below the Medical Devices & Instruments industry median of 5.00. Nephros' overall GF Score™ is 63/100 with 5 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 Nephros (NEPH), the current Piotroski F-Score is 3 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 Nephros (NEPH) Overvalued in 2026?
Based on GuruFocus' analysis, Nephros stock appears to be overvalued.
The current stock price of $3.35 is trading 16.7% above its estimated GF Value™ of $2.87.
GuruFocus considers Nephros to be Modestly Overvalued.
Key valuation signals for NEPH:
Piotroski F-Score: 3 (25% below median its 10-year median of 4.00)
GF Value™: $2.87 vs. price of $3.35 (16.7% above fair value)
Industry Position: 40% below the Medical Devices & Instruments median (#620 of 805)
No single metric tells the full story. See the NEPH stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Nephros Inc is a commercial-stage company that develops and sells high-performance water solutions to the medical and commercial markets. In medical markets, it sells water filtration products and waterborne pathogen detection products. In commercial markets, the company manufactures and sells water filters that improve the taste and odor of water and reduce biofilm, bacteria, and scale build-up in downstream equipment. The company's subsidiary is engaged in the development of its second-generation hemodiafiltration system and other products focused on improving therapies for patients with renal disease. The company generates almost all of revenue from product sales and a small amount from royalty revenue and other revenues.
63GF Score
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