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Sionna TherapeuticsSION +4.03%12 3-Year Share Buyback Ratio is -1.80 as of Mar. 2026. GuruFocus rates SION with a GF Score™ of 12/100. The stock has 3 warning signs investors should review. Among 1,197 Biotechnology companies, Sionna Therapeutics ranks better than 78.7% on this metric.
Shares Outstanding (EOP) are shares that have been authorized, issued, and purchased by investors and are held by them.
3-Year Share Buyback Ratio measures the average annual proportion of a company's outstanding shares repurchased over the past three years. It is calculated as the annualized percentage change in shares outstanding from three years ago to the current year. A positive ratio may indicate share buybacks over the period, while a zero or negative ratio may reflect no repurchases or potential share issuance. Sionna Therapeutics's current 3-Year Share Buyback Ratio was -1.80%.
The historical rank and industry rank for Sionna Therapeutics's 3-Year Share Buyback Ratio or its related term are showing as below:
SION'
s 3-Year Share Buyback Ratio Range Over the Past 10 Years
Min: -1.8 Med: -1.8 Max: -1.8
Current: -1.8
During the past 4 years, Sionna Therapeutics's highest 3-Year Share Buyback Ratio was -1.80%. The lowest was -1.80%. And the median was -1.80%.
SION's 3-Year Share Buyback Ratio is ranked better than 78.7% of 1197
companies
in the Biotechnology industry
Industry Median: -11.6
vs SION: -1.80
Sionna Therapeutics (NAS:SION) 3-Year Share Buyback Ratio Explanation
A negative number means the company might be issuing new shares. A positive number indicates that the company is buying back shares.
Be Aware
Investors usually like share buybacks. But as pointed by Warren Buffett, only if a company buys back shares at the prices below the stock's intrinsic value, it rewards remaining shareholders. If a company buys its overvalued stocks back, it destroys shareholder value.
Sionna Therapeutics 3-Year Share Buyback Ratio Related Terms
SION vs HRMY, VRDN, URGN: 3-Year Share Buyback Ratio Comparison
For the Biotechnology subindustry, Sionna Therapeutics's 3-Year Share Buyback Ratio, along with its competitors' market caps and 3-Year Share Buyback Ratio 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.
Sionna Therapeutics 3-Year Share Buyback Ratio vs Biotechnology Industry
For the Biotechnology industry and Healthcare sector, Sionna Therapeutics's 3-Year Share Buyback Ratio distribution charts can be found below:
* The bar in red indicates where Sionna Therapeutics's 3-Year Share Buyback Ratio falls into.
Sionna Therapeutics 3-Year Share Buyback Ratio Calculation
This is the annualized percentage change in shares outstanding from three years ago to the current year. The annualized percentage change is calculated with expontential compound based on the latest four years of annual data on Shares Outstanding (EOP).
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 dividends per share growth rate.
What does a 3-Year Share Buyback Ratio of -1.80 mean?
Sionna Therapeutics (SION) has a 3-Year Share Buyback Ratio of -1.80 as of Mar. 2026. The 3-Year Share Buyback Ratio measures the average annual proportion of a company's outstanding shares repurchased over the past three years. It is calculated as the annualized percentage change in shares outstanding from three years ago to the current year. View historical data for Sionna Therapeutics and its competitors. According to the industry distribution chart, Sionna Therapeutics ranks #255 out of 1197 companies in the Biotechnology industry, placing it in the top 21.3%.
Is Sionna Therapeutics' 3-Year Share Buyback Ratio too high?
Sionna Therapeutics' current 3-Year Share Buyback Ratio is -1.80. Based on the distribution chart, Sionna Therapeutics ranks #255 out of 1197 companies in the Biotechnology industry, which is in the top quartile — a strong position relative to peers. Overall, Sionna Therapeutics has a GF Score™ of 12/100, reflecting its overall financial health beyond just this single metric.
How does Sionna Therapeutics' 3-Year Share Buyback Ratio compare to HRMY and VRDN?
According to the Biotechnology industry distribution chart, Sionna Therapeutics ranks #255 out of 1197 companies for 3-Year Share Buyback Ratio. This places Sionna Therapeutics in the top 21% of its industry — outperforming the majority of peers. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good 3-Year Share Buyback Ratio for a Biotechnology company?
A good 3-Year Share Buyback Ratio depends on the Biotechnology industry context. However, 3-Year Share Buyback Ratio 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 Share Buyback Ratio mean?
A high 3-Year Share Buyback Ratio can signal that a stock is expensive relative to its fundamentals. The 3-Year Share Buyback Ratio measures the average annual proportion of a company's outstanding shares repurchased over the past three years. It is calculated as the annualized percentage change in shares outstanding from three years ago to the current year. View historical data for Sionna Therapeutics and its competitors. Sionna Therapeutics's current 3-Year Share Buyback Ratio is -1.80. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Sionna Therapeutics stock overvalued right now?
Sionna Therapeutics (SION) has a current 3-Year Share Buyback Ratio of -1.80. The current 3-Year Share Buyback Ratio is -1.80. Sionna Therapeutics' overall GF Score™ is 12/100 with 3 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is 3-Year Share Buyback Ratio calculated?
3-Year Share Buyback Ratio is calculated from a company's financial statements. For Sionna Therapeutics (SION), the current 3-Year Share Buyback Ratio is -1.80 as of Mar. 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.
Sionna Therapeutics Inc is a clinical-stage biopharmaceutical company on a mission to revolutionize the current treatment paradigm for cystic fibrosis (CF) patients by developing novel medicines that normalize the function of the cystic fibrosis transmembrane conductance regulator (CFTR) protein to deliver clinically meaningful benefits to CF patients. CF is a progressive and life-threatening genetic disease caused by inherited mutations in the CFTR gene, which heads to insufficient CFTR function. The Company is managed as one operating segment focused on the research and development of cystic fibrosis therapies.
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