SuperworthProthena Corp Public market cap PRTA
Share price times shares outstanding: what the whole company sells for, since 2013.
- Today, Oct 23, 2026
- $421M
- Highest close in our data
- $4.1B
- May 2023
Prothena Corp Public is worth $421M at the close on Oct 23, 2026, at $8.20 a share.
That is down 20% over the last year and down 83% over five years.
Its highest close in our data was $4.1B in May 2023.
Market cap over time
Year by year
| Year | End of year | Low | High | Change |
|---|---|---|---|---|
| 2026 so far | $421M | $421M | $586.8M | −18% |
| 2025 | $513.5M | $247.1M | $851M | −37% |
| 2024 | $814.7M | $688.2M | $2.2B | −58% |
| 2023 | $2B | $1.8B | $4.1B | −33% |
| 2022 | $2.9B | $1.1B | $3.1B | +27% |
| 2021 | $2.3B | $447.5M | $3.5B | +380% |
| 2020 | $479.5M | $358M | $612.8M | −25% |
| 2019 | $638.3M | $274.9M | $638.3M | +56% |
| 2018 | $408.6M | $354.4M | $1.7B | −72% |
| 2017 | $1.4B | $1.4B | $2.6B | −15% |
| 2016 | $1.7B | $993.3M | $2.2B | −21% |
| 2015 | $2.1B | $549.6M | $2.4B | +267% |
| 2014 | $585.5M | $380.3M | $996.1M | −2% |
| 2013 | $594.5M | $174.3M | $617M | n/a |
Against its peers
Companies in Drug Manufacturers - General nearest Prothena Corp Public's size, closest first, today.
| Company | Market cap |
|---|---|
| PRTAProthena Corp Public | $421M |
| ARVNArvinas | $477.3M |
| PBYIPuma Biotechnology | $568.9M |
| IRWDIronwood Pharmaceuticals | $571.7M |
| ZVRAZevra Therapeutics | $582.6M |
| CRMDCorMedix | $611.9M |
| COLLCollegium Pharmaceutical | $747.5M |
| NATRNatures Sunshine Products | $213.8M |
| ABUSArbutus Biopharma | $831M |
| AMPHAmphastar Pharmaceuticals | $1.1B |
| OMEROmeros | $1.2B |
| Peer median | $597.2M |
What the market cap tells you
Share price times shares outstanding: what the whole company sells for today.
Size, not quality. Large caps move slower and are covered more. That is all it tells you.
More on Prothena Corp Public
Valuation data, not investment advice. Prices as of . Reported figures come from the company's filings with the SEC.