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ProthenaPRTA -5.98%74 3-Year Book Growth Rate is -24.10% as of Jun. 2026. GuruFocus rates PRTA with a GF Score™ of 74/100 and a GF Value™ of $12.78 (Possible Value Trap). The stock has 2 warning signs investors should review. Among 1,123 Biotechnology companies, Prothena ranks worse than 67.23% on this metric.
During the past 12 months, Prothena's average Book Value per Share Growth Rate was -8.00% per year.
During the past 3 years, the average Book Value per Share Growth Rate was -24.10% per year.
During the past 5 years, the average Book Value per Share Growth Rate was 0.50% per year.
During the past 10 years, the average Book Value per Share Growth Rate was -3.00% per year.
Please click Growth Rate Calculation Example (GuruFocus) to see how GuruFocus calculates Wal-Mart Stores Inc (WMT)'s revenue growth rate. You can apply the same method to get the average Book Value per Share growth rate.
During the past 13 years, the highest 3-Year average Book Value per Share Growth Rate of Prothena was 31.40% per year. The lowest was -24.20% per year. And the median was 0.00% per year.
Prothena (NAS:PRTA) 3-Year Book Growth Rate Explanation
Book Value per Share is the ratio of equity available to common shareholders divided by the shares outstanding. Book value per share effectively indicates a firm's net asset value on a per-share basis. It can be used by investors to gauge whether a stock price is undervalued by comparing it to the firm's market value per share. Theoretically, it is what the shareholders will receive if the company is liquidated.
Prothena 3-Year Book Growth Rate Related Terms
PRTA vs EVMN, EDIT, CCCC: 3-Year Book Growth Rate Comparison
For the Biotechnology subindustry, Prothena's 3-Year Book Growth Rate, along with its competitors' market caps and 3-Year Book Growth Rate 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 3-Year Book Growth Rate vs Biotechnology Industry
For the Biotechnology industry and Healthcare sector, Prothena's 3-Year Book Growth Rate distribution charts can be found below:
* The bar in red indicates where Prothena's 3-Year Book Growth Rate falls into.
This is the 3-year average growth rate of Book Value per Share. The growth rate is calculated using exponential compounding based on the latest four year annual data.
Please click Growth Rate Calculation Example (GuruFocus) to see how GuruFocus calculates Wal-Mart Stores Inc (WMT)'s revenue growth rate. You can apply the same method to get the average Book Value per Share growth rate.
What does a 3-Year Book Growth Rate of -24.10% mean?
Prothena (PRTA) has a 3-Year Book Growth Rate of -24.10% as of Jun. 2026. 3-Year Book Growth Rate is the 3-year average growth rate of Book Value per Share. View historical data for Prothena and its competitors. According to the industry distribution chart, Prothena ranks #755 out of 1123 companies in the Biotechnology industry, placing it in the top 67.2%.
Is Prothena's 3-Year Book Growth Rate too high?
Prothena's current 3-Year Book Growth Rate is -24.10%. Based on the distribution chart, Prothena ranks #755 out of 1123 companies in the Biotechnology industry, which is below the industry midpoint. Overall, Prothena has a GF Score™ of 74/100 and is considered Possible Value Trap, reflecting its overall financial health beyond just this single metric.
How does Prothena's 3-Year Book Growth Rate compare to EVMN and EDIT?
According to the Biotechnology industry distribution chart, Prothena ranks #755 out of 1123 companies for 3-Year Book Growth Rate. 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 3-Year Book Growth Rate for a Biotechnology company?
A good 3-Year Book Growth Rate depends on the Biotechnology industry context. However, 3-Year Book Growth Rate 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 3-Year Book Growth Rate mean?
A high 3-Year Book Growth Rate can signal that a stock is expensive relative to its fundamentals. 3-Year Book Growth Rate is the 3-year average growth rate of Book Value per Share. View historical data for Prothena and its competitors. Prothena's current 3-Year Book Growth Rate is -24.10%. 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 Possible Value Trap. The stock's GF Value™ is $12.78, compared to a current price of $8.35 — trading 34.7% below its estimated fair value. The current 3-Year Book Growth Rate is -24.10%. 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 3-Year Book Growth Rate calculated?
3-Year Book Growth Rate is calculated from a company's financial statements. For Prothena (PRTA), the current 3-Year Book Growth Rate is -24.10% as of Jun. 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 $8.35 is trading 34.7% below its estimated GF Value™ of $12.78.
GuruFocus considers Prothena to be Possible Value Trap.
Key valuation signals for PRTA:
3-Year Book Growth Rate: -24.10%
GF Value™: $12.78 vs. price of $8.35 (34.7% 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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