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ProthenaPRTA +6.66%74 Net Cash per Share is $5.27 as of Jun. 2026, which is 65% above its 10-year median of 3.20. 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 784 Biotechnology companies, Prothena ranks better than 85.33% on this metric.
Prothena (NAS:PRTA) Net Cash per Share Explanation
Ben Graham invested in situations where the company's stock price was lower than its net-cash. He assigned some value to the company's other current asset. The value is called Net Current Asset Value (NCAV). One research study, covering the years 1970 through 1983 showed that portfolios picked at the beginning of each year, and held for one year, returned 29.4 percent, on average, over the 13-year period, compared to 11.5 percent for the S&P 500 Index. Other studies of Graham's strategy produced similar results.
You can find companies that are traded below their Net Current Asset Value (NCAV) with our Net-Net screener.
Prothena Net Cash per Share Related Terms
Prothena Net Cash per Share Historical Data
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The historical data trend for Prothena's Net Cash per Share 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.
PRTA vs KYTX, QTTB, RZLT: Net Cash per Share Comparison
For the Biotechnology subindustry, Prothena's Price-to-Net-Cash, along with its competitors' market caps and Price-to-Net-Cash 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 Price-to-Net-Cash vs Biotechnology Industry
For the Biotechnology industry and Healthcare sector, Prothena's Price-to-Net-Cash distribution charts can be found below:
* The bar in red indicates where Prothena's Price-to-Net-Cash falls into.
In the calculation of a company's Net Cash per Share, assets other than cash and short term investments are considered to be worth nothing. But the company has to pay its debt and other liabilities in full. This is an extremely conservative way of valuation. Most companies have negative Net Cash per Share. But sometimes a company's price may be lower than its net-cash.
Prothena's Net Cash per Share for the fiscal year that ended in Dec. 2025 is calculated as
* 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 Net Cash per Share of $5.27 as of Jun. 2026. Net cash per share equals the per-share value of cash and equivalents less total liabilities and minority interest. View historical data on Prothena and its competitors. This is 65% above median its historical median of 3.20. Over the past decade, Prothena's Net Cash per Share has ranged from 1.10 to 9.18. According to the industry distribution chart, Prothena ranks #115 out of 784 companies in the Biotechnology industry, placing it in the top 14.7%.
Is Prothena's Net Cash per Share too high?
Prothena's current Net Cash per Share of $5.27 is 65% above median its 10-year median of 3.20. Over the past 10 years, this metric has ranged from a low of 1.10 to a high of 9.18. The Biotechnology industry median Net Cash per Share is 5.16. Prothena's value of $5.27 is 2.2% above this industry median. Based on the distribution chart, Prothena ranks #115 out of 784 companies in the Biotechnology industry, which is in the top quartile — a strong position relative to peers. 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 Net Cash per Share compare to KYTX and QTTB?
According to the Biotechnology industry distribution chart, Prothena ranks #115 out of 784 companies for Net Cash per Share. This places Prothena in the top 15% of its industry — outperforming the majority of peers. The industry median Net Cash per Share is 5.16. Prothena's value of $5.27 is 2.2% above this benchmark. Historically, Prothena's own Net Cash per Share has ranged from 1.10 to 9.18 over the past decade. While the company's 10-year median is 3.20 vs. the industry median of 5.16, Prothena 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 Net Cash per Share for a Biotechnology company?
The median Net Cash per Share among Biotechnology companies is 5.16, based on 784 companies in the industry. Companies in the top quartile (top 25%) have a Net Cash per Share significantly above this median, while those in the bottom quartile fall well below. However, Net Cash per Share should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Prothena's current Net Cash per Share of $5.27 is 2.2% 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 Net Cash per Share mean?
A high Net Cash per Share can signal that a stock is expensive relative to its fundamentals. Net cash per share equals the per-share value of cash and equivalents less total liabilities and minority interest. View historical data on Prothena and its competitors. For the Biotechnology industry, the median Net Cash per Share is 5.16 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Prothena's current Net Cash per Share is $5.27, which is 65% above median its own 10-year median of 3.20. 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 Net Cash per Share is $5.27, which is 65% above median its 10-year median of 3.20 and 2.2% above the Biotechnology industry median of 5.16. 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 Net Cash per Share calculated?
Net Cash per Share is calculated from a company's financial statements. For Prothena (PRTA), the current Net Cash per Share is $5.27 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 $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:
Net Cash per Share: $5.27 (65% above median its 10-year median of 3.20)
GF Value™: $12.97 vs. price of $9.29 (28.4% below fair value)
Industry Position: 2.2% above the Biotechnology median (#115 of 784)
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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