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ProthenaPRTA +6.66%74 EV-to-OCF is -3.26 as of Aug. 20, 2026. GuruFocus rates PRTA with a GF Score™ of 74/100 and a GF Value™ of $12.97 (Modestly Undervalued). The stock has 2 warning signs investors should review. Among 1,408 Biotechnology companies, Prothena ranks worse than 54.69% on this metric.
EV-to-OCF is calculated as enterprise value divided by its cash flow from operations. As of today, Prothena's Enterprise Value is $195.72 Mil.
Prothena's Cash Flow from Operations for the trailing twelve months (TTM) ended in Jun. 2026 was $-60.05 Mil. Therefore, Prothena's EV-to-OCF for today is -3.26.
The historical rank and industry rank for Prothena's EV-to-OCF or its related term are showing as below:
PRTA'
s EV-to-OCF Range Over the Past 10 Years
Min: -91.98 Med: -3.23 Max: 61.89
Current: -3.26
During the past 13 years, the highest EV-to-OCF of Prothena was 61.89. The lowest was -91.98. And the median was -3.23.
PRTA's EV-to-OCF is ranked worse than 54.69% of 1408
companies
in the Biotechnology industry
Industry Median: -3.66
vs PRTA: -3.26
EV-to-OCF is a valuation multiple that allows analysts and investors to compare stocks, preferably in the same sector or industry. This important multiple is often used in conjunction with, or as an alternative to, the PE Ratio (TTM) to determine the fair market value of a company.
EV-to-OCF is a valuation multiple that allows analysts and investors to compare stocks, preferably in the same sector or industry. This important multiple is often used in conjunction with, or as an alternative to, the PE Ratio (TTM) to determine the fair market value of a company.
Prothena's share price for today is $9.29.
Prothena's Earnings per Share (Diluted) for the trailing twelve months (TTM) ended in Jun. 2026 adds up the quarterly data reported by the company within the most recent 12 months, which was $-0.840.
* 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.
Enterprise Value is used because it is a more complete measure in reflecting how much an investor pays when buying a company. Cash Flow from Operations is an important financial metric because it represents the cash generated from operating activities at a company's disposal. Companies with a low EV-to-OCF ratio, combined with a strong balance sheet are generally considered as undervalued.
Prothena EV-to-OCF Related Terms
Prothena EV-to-OCF Historical Data
* Premium members only.
The historical data trend for Prothena's EV-to-OCF 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, Prothena's EV-to-OCF, along with its competitors' market caps and EV-to-OCF 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.
Prothena EV-to-OCF vs Biotechnology Industry
For the Biotechnology industry and Healthcare sector, Prothena's EV-to-OCF distribution charts can be found below:
* The bar in red indicates where Prothena's EV-to-OCF falls into.
Prothena's current Enterprise Value is $195.72 Mil.
Prothena's Cash Flow from Operations for the trailing twelve months (TTM) ended in Jun. 2026 adds up the quarterly data reported by the company within the most recent 12 months, which was $-60.05 Mil.
* 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.
Prothena (PRTA) has a EV-to-OCF of -3.26 as of Aug. 20, 2026. According to the industry distribution chart, Prothena ranks #770 out of 1408 companies in the Biotechnology industry, placing it in the top 54.7%.
Is Prothena's EV-to-OCF too high?
Prothena's current EV-to-OCF is -3.26. Based on the distribution chart, Prothena ranks #770 out of 1408 companies in the Biotechnology industry, which is below the industry midpoint. Overall, Prothena has a GF Score™ of 74/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Prothena's EV-to-OCF compare to KYTX and QTTB?
According to the Biotechnology industry distribution chart, Prothena ranks #770 out of 1408 companies for EV-to-OCF. This places Prothena in the lower half of its industry. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good EV-to-OCF for a Biotechnology company?
A good EV-to-OCF depends on the Biotechnology industry context. However, EV-to-OCF should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high EV-to-OCF mean?
A high EV-to-OCF can signal that a stock is expensive relative to its fundamentals. Prothena's current EV-to-OCF is -3.26. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Prothena stock overvalued right now?
Based on GuruFocus' analysis, Prothena (PRTA) is currently considered Modestly Undervalued. The stock's GF Value™ is $12.97, compared to a current price of $9.29 — trading 28.4% below its estimated fair value. The current EV-to-OCF is -3.26. Prothena's overall GF Score™ is 74/100 with 2 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is EV-to-OCF calculated?
EV-to-OCF is calculated from a company's financial statements. For Prothena (PRTA), the current EV-to-OCF is -3.26 as of Aug. 20, 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 Prothena (PRTA) Overvalued in 2026?
Based on GuruFocus' analysis, Prothena stock appears to be undervalued.
The current stock price of $9.29 is trading 28.4% below its estimated GF Value™ of $12.97.
GuruFocus considers Prothena to be Modestly Undervalued.
Key valuation signals for PRTA:
EV-to-OCF: -3.26
GF Value™: $12.97 vs. price of $9.29 (28.4% below fair value)
No single metric tells the full story. See the PRTA stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Prothena Corp PLC is a late-stage clinical biotechnology company that focuses on protein dysregulation and a pipeline of investigational therapeutics with the potential to change the course of devastating neurodegenerative and rare and peripheral amyloid diseases. Prothena is developing and applying its proprietary CYTOPE technology to target a broad spectrum of intracellular disease pathways in the brain and periphery. The company's pipeline includes both wholly-owned and partnered programs like Prasinezumab, Coramitug (PRX004), BMS-986446 (PRX005), PRX019, TDP-43 CYTOPE, and PRX012-TfR, being developed for the potential treatment of Parkinson's disease, ATTR amyloidosis with cardiomyopathy, Alzheimer's disease, Amyotrophic lateral sclerosis (ALS), and other neurodegenerative diseases.
74GF Score
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