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PRTA · Prothena Corp Public Ltd Co

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$8.86 -0.22 (-2.42%) At close · Aug 14
Market Cap
$454.85M
Shares
51.34M

Price & Indicators

20d MA 50d MA 200d MA Earnings Filing Insider Congress Investor day
Close$8.86 Open$9.04 Day$8.84–9.15 52W close$7.91–11.51 Avg vol 30d523K Short int8.2M · 15.9% float · 14.0d Short vol76% Last earningsFeb 19, 2026 DataJan 2020–Aug 2026 Filing10-Q · Aug 6

Up next

Next earnings call
Feb 22, 2027 Est · unconfirmed · in 27 wks
FQ3-26 quarter ends
~Sep 30, 2026 Est
filed Aug 6, 2026

AI Brief

TL;DR.

Bullish
    Bearish

      AI-generated from the earnings call and 8-K · may contain errors · not investment advice

      Ask ALVIS about this →

      Equibles Rating

      blended score · not investment advice
      Overall
      Sell
      SellHoldBuy
      Technical Neutral Momentum Weak Sentiment Bullish Fundamentals Fair Quant / Vol Very High
      Market backdrop VIX 14.3 · calm Equity put/call 0.52
      Technical
      price trend
      Neutral
      50 / 200-day cross No cross
      Price vs 200-day avg −7%
      below
      Price vs 50-day avg −0%
      below
      RSI (14) 50
      neutral
      MACD trend Positive
      52-week position 26%
      mid-range
      Volume (OBV) Confirms
      volume backs price
      Momentum
      relative strength
      Weak
      1-month return +2%
      trailing
      6-month return −2%
      trailing
      YTD return −7%
      this year
      Relative strength −16%
      vs S&P · 6-mo
      Sentiment
      smart money
      Bullish
      Trend (MA cross) No cross
      50d $9 › 200d $10 — 200d above 50d
      Institutional flow Flat
      0% holders QoQ · +29 funds added
      Insider flow Accumulating
      Net +$3.4M over 90 days · 0% sells
      Short interest Falling
      15.92% of float · ▼ -0.3% MoM · 14.0 days cover
      Volume signal Normal
      Volume near normal
      Institution breadth Steady
      186 holders — mid 3-yr range
      Squeeze score 63
      elevated · 0–100
      Fundamentals
      Fair
      Revenue growth −15%
      Y/Y
      EPS growth −100%
      Y/Y
      Buyback $77.7M
      remaining
      Balance sheet $307.5M
      net cash
      Quant / Vol
      risk profile
      Very High
      Volatility 47%
      annualized · 1-yr
      Max drawdown −31%
      past year
      ATR 4.7%
      of price · 14-day

      Blended from price, momentum, positioning, fundamentals & volatility · daily-close · not investment advice. Market backdrop is context, not part of the score.

      Guidance & track record

      Latest guidance · from the 8-K filed Feb 19, 2026
      full year 2026
      Net cash used in operating and investing activities $50M – $55M
      Non-cash share-based compensation expense $24M
      Net loss $67M – $72M
      end of 2026
      Cash, cash equivalents, and restricted cash $255M
      Prior guidance period ended · from the 8-K filed Nov 6, 2025
      Net cash used in operating and investing activities · full year 2025 $170M – $178M
      Cash, cash equivalents, and restricted cash · end of 2025 $298M
      Non-cash share-based compensation expense · full year 2025 $36M
      Net loss · full year 2025 $240M – $248M

      Guidance from company 8-Ks · delivered figures from as-reported statements · no analyst estimates involved.

      Technicals

      trend & momentum for long-term holders Neutral
      1 · 5 · 1
      50 / 200-day cross
      No cross Neutral
      Price vs 200-day avg
      −7% Bearish
      Price vs 50-day avg
      −0% Neutral
      RSI (14)
      50 Neutral
      MACD trend
      Positive Bullish
      52-week position
      26% Neutral
      Volume (OBV)
      Confirms Neutral
      Market signals — smart money & positioning
      Bullish · 2 of 6
      Trend (MA cross) No cross
      50d $9 › 200d $10 — 200d above 50d
      Institutional flow Flat
      0% holders QoQ · +29 funds added
      Insider flow Accumulating
      Net +$3.4M over 90 days · 0% sells
      Short interest Falling
      15.92% of float · ▼ -0.3% MoM · 14.0 days cover
      Volume signal Normal
      Volume near normal
      Institution breadth Steady
      186 holders — mid 3-yr range
      Price context
      position in its 52-week range
      Range low $8 Now $9 · 26% Range high $12
      vs 200-day avg -7% vs 50-day avg 0%

      Illustrative technical + ownership context — a signal mix, not investment advice.

      Versus peers

      Biotechnology — same industry group
      Open screener →
      Company Mkt cap YTD Rev growth Y/Y P/E Short % shares
      PRTA
      Prothena Corp Public Ltd Co
      this stock
      $454.85M -7.2% -14.8% 15.9%
      ONC
      BeOne Medicines Ltd.
      $513.62B +14.4% +22179.2% 789.7 0.1%
      VRTX
      Vertex Pharmaceuticals Inc / Ma
      $128.19B +11.6% +46.2% 29.5 1.6%
      REGN
      Regeneron Pharmaceuticals, Inc.
      $82.72B +4.1% +20.8% 19.9 3.3%
      ARGX
      Argenx SE
      $52.94B +1.2% 2.1%

      Peers by industry group · P/E from as-reported trailing EPS · short % is of shares outstanding

      At a glance

      key data from every section
      Ownership
      Institutional Holders Reducing
      Holders
      186
      % held
      91.7%
      Net QoQ
      -399.3K sh
      Top holder
      FMR LLC
      Held Float
      View
      Held by Funds
      Fund positions
      59
      View
      Short & Settlement
      Short Interest Falling
      Shares short
      8.2M
      Days to cover
      14.0d
      Change
      -24.5K sh
      View
      Short Volume
      Short vol %
      76%
      As of
      Aug 14, 2026
      Short Total
      View
      Fails to Deliver
      FTD shares
      397
      Value
      $3.7K
      As of
      Jul 13, 2026
      View
      Off-Exchange
      Off-exchange %
      30.8%
      Week of
      Jul 6, 2026
      Off-exch Lit
      View
      Smart Money
      Insider Trades Net buying
      Net (90d)
      +$3.4M
      Buyers / Sellers
      1 / 0
      Buyers Sellers
      View
      Financials
      Financials
      Revenue (FY)
      $9.7M
      Net income (FY)
      $-244.1M
      EPS diluted
      $-4.53
      View
      Buybacks
      Authorized
      $100.0M
      Remaining
      $77.7M
      Spent Remaining
      View
      Filings
      SEC Filings
      Latest
      8-K
      Filed
      Aug 6, 2026
      This year
      10
      View
      Proposed Sales
      Value
      $64.9K
      Shares
      7.7K
      Filed
      Jul 29, 2026
      View
      Earnings & Events
      Earnings Calls
      Last call
      Feb 19, 2026
      View
      Investor Relations
      Latest news
      Prothena Reports Second Quarter 2…
      Published
      Aug 6, 2026
      View

      Performance

      5D 20D 120D MTD YTD
      PRTA +1.1% +2.3% -2.3% +9.1% -7.2%
      SPY +0.4% +4.5% +13.8% +3.9% +13.9%
      vs SPY +0.7% -2.1% -16.1% +5.2% -21.1%

      Capital returns

      Buyback program · as of Jul 30, 2026
      Authorized
      $100.00M
      Spent (derived)
      $22.30M
      Remaining
      $77.70M
      Spent Remaining

      Dividends per share over the trailing 365 days by ex-date · buyback figures as last reported in SEC filings ("spent" derived as authorized − remaining; when several programs run concurrently, authorized is their combined total per the newest filing) · components shown separately — trailing-year buyback spend isn't tracked, so no combined shareholder yield is derived.

      Key facts CIK 1559053 CUSIP G72800108 13F (30d) 181 filings 177 filers Visit website Investor relations