PRTA

Prothena Corporation plc
NasdaqGSUSDEQUITY Healthcare DELAYED
Last price
8.16
▼ 0.11 (1.33%)
MARKET · —

Price

1D — H — L — Range — Vol —
Drag pan · Pinch zoom · Hold crosshair · pick a tool then drag to draw
Open
8.28
Prev close
8.27
Day high
8.28
Day low
7.80
Volume
509.61K
Market cap
$411.72M
P/E (TTM)
—
52W range
7.73 – 11.80

Day trading desk

Current session · delayed
Gap from prior close
+0.12%
Prior close 8.27
VWAP
8.02
+1.75% from price
Relative volume
1.92×
Unusually busy
Session range
6.15%
7.80 – 8.28
Position in range
75%
Near session high
ATR (14D)
0.41
5.05% of price
Prior day high
8.37
PDH
Prior day low
7.91
PDL
Bid / ask spread
—
Quote not published
Session volume
917.36K
Avg 477.69K

VWAP and the session figures are computed from the delayed intraday series on this page, so they lag the live tape and will not match a broker's real-time VWAP exactly. Turn on Prior day H/L/C, Opening range and Volume profile in the chart's Studies menu to see these levels drawn on price.

Trailing performance

Price return · vs SPY
Returnvs SPY
1W
-8.66% -10.6%
1M
-18.33% -19.5%
3M
-18.58% -23.1%
6M
-22.59% -40.8%
YTD
-16.02% -30.3%
1Y
-19.15% -35.6%
3Y
-83.38% -165.6%
5Y
— —

Price return only. Dividends are not reinvested, so total return on a dividend payer will be higher than shown.

Unusual options activity

Account required
Nothing crossed the thresholds in the expiries we scanned.
That is the normal state — most contracts trade well inside their existing open interest.
Free account required

Contracts trading at or above their open interest, ranked by notional and where the print landed.

Free account

5 more panels on PRTA open with an account.

Options chains and analytics, valuation ratios, insider filings, analyst targets and ownership. No card, no trial, nothing to cancel.

Insider net activity

6m · Form 4 rollup
Net shares
+2.10M
Net buying
Buy transactions
19
2.11M shares
Sell transactions
2
16.05K shares
Net transactions
+21
Buys less sells
Sell : buy shares
0.0 : 1
Mixed
Insider-held shares
11.47M
Total on file
Bought 2.11MSold 16.05K

Insider transactions

Account required
DateInsiderAction SharesValueHeld
Sep 29, 26
SCULLY WILLIAM P
Beneficial Owner of more than 10% of a Class of Security
BUY 162.00K $1.41M Indirect
Sep 28, 26
SCULLY WILLIAM P
Beneficial Owner of more than 10% of a Class of Security
BUY 103.50K $889.87K Indirect
Sep 18, 26
SCULLY WILLIAM P
Beneficial Owner of more than 10% of a Class of Security
BUY 100.00K $843.46K Direct
Sep 2, 26
SCULLY WILLIAM P
Beneficial Owner of more than 10% of a Class of Security
BUY 27.00K $255.74K Direct
Aug 20, 26
SCULLY WILLIAM P
Beneficial Owner of more than 10% of a Class of Security
BUY 50.00K $439.43K Direct
Aug 18, 26
SCULLY WILLIAM P
Beneficial Owner of more than 10% of a Class of Security
STOCK 627.55K $0 Direct
Aug 7, 26
SCULLY WILLIAM P
Beneficial Owner of more than 10% of a Class of Security
BUY 37.50K $323.22K
Jul 29, 26
KINGSTON ANNE EVANS
Officer
SELL 7.66K $64.92K Direct
Jul 29, 26
ISAACS MICHAEL JOHN
General Counsel
SELL 8.39K $71.06K Direct
Jul 28, 26
WALKER KARIN LORRAINE
Officer
— 15.00K — Direct
Jul 28, 26
NGUYEN TRAN BRYAN
Chief Financial Officer
— 57.00K — Direct
Jul 28, 26
KINNEY GENE G PH.D.
Chief Executive Officer
— 84.00K — Direct
Jul 28, 26
ZAGO WAGNER M
Officer
— 51.00K — Direct
Jul 28, 26
SMITH BRANDON S
Chief Operating Officer
— 78.00K — Direct
What this is, and what it is not

These are SEC Form 4 filings — officers, directors and 10% owners reporting their own trades in the company's stock. Filing is due within two business days of the transaction, so this lags reality by days, and the provider adds its own lag on top.

A sale is not automatically bearish. Executives sell on scheduled 10b5-1 plans, to cover tax on vesting equity, and to diversify. Purchases with cash are generally the more informative signal, and they are far rarer.

This does not include congressional or senate trading. That comes from STOCK Act disclosures filed with the Senate eFD system and the House Clerk, which this data source does not carry.

Free account required

Officer and director trades in their own stock, straight from Form 4 filings.

Insider holders

10 reporting
NameRelationShares heldLatest
ECOR1 CAPITAL, L.L.C.
Beneficial Owner of more than 10% of a Class of Security — Sale
ISAACS MICHAEL JOHN
General Counsel 35.74K Sale
KINGSTON ANNE EVANS
Officer 55.78K Sale
KINNEY GENE G PH.D.
Chief Executive Officer 68.79K Conversion of Exercise of derivative security
MALECEK MICHAEL J.
Officer 80.00K Stock Award(Grant)
NGUYEN TRAN BRYAN
Chief Financial Officer 40.20K Conversion of Exercise of derivative security
SCULLY WILLIAM P
Beneficial Owner of more than 10% of a Class of Security — Purchase
SMITH BRANDON S
Chief Operating Officer 52.00K Conversion of Exercise of derivative security
SWANSON CHAD PH.D.
Officer 40.73K Conversion of Exercise of derivative security
ZAGO WAGNER M
Officer 34.00K Conversion of Exercise of derivative security

Fundamentals

TTM · reported
Market cap$411.72M
Enterprise value$130.52M
Revenue (TTM)$54.53M
Gross profit$-10.42M
EBITDA$-59.04M
Net income$-43.99M
EPS (TTM)$-0.79
Free cash flow$-54.22M
Total cash$288.19M
Total debt$6.99M
Book value / share$5.54
Shares outstanding51.34M
Float34.54M
Short % of float20.05%
Dividend yield0.00%
Beta (5Y)-0.29

Valuation & profitability ratios

Account required
Trailing P/E—
Forward P/E-5.28
PEG ratio—
Price / sales—
Price / book1.45
EV / revenue2.39
EV / EBITDA-2.21
Gross margin-19.11%
Operating margin-1850.20%
Profit margin-80.68%
Return on equity-14.39%
Return on assets-10.67%
Debt / equity2.44
Current ratio25.05
Free account required

Fourteen ratios including P/E, PEG, EV/EBITDA, margins and return on equity.

Financial statements

As reported · 5 years · 6 quarters
Blank means not reported, not zero
Line item2025202420232022YoY
Total revenue $9.68M$135.16M$91.37M$53.91M -92.8%
Operating revenue $9.68M$135.16M$91.37M$53.91M -92.8%
Research & development $134.85M$222.52M$220.57M$135.56M -39.4%
Selling, general & admin $59.39M$67.20M$61.84M$49.90M -11.6%
Total operating expense $194.24M$289.72M$282.41M$185.46M -33.0%
Operating income -$184.56M-$154.56M-$191.04M-$131.56M -19.4%
Net interest income $14.14M$25.82M$31.01M$6.35M -45.2%
Pre-tax income -$200.83M-$128.93M-$160.48M-$125.61M -55.8%
Tax provision $43.26M-$6.62M-$13.45M-$8.66M +753.5%
Net income -$244.09M-$122.31M-$147.03M-$116.95M -99.6%
Net income to common -$244.09M-$122.31M-$147.03M-$116.95M -99.6%
Basic EPS -4.53-2.27-2.76-2.47 -99.6%
Diluted EPS -4.53-2.27-2.76-2.47 -99.6%
EBIT -$184.56M-$154.56M-$191.04M-$131.56M -19.4%
EBITDA -$183.66M-$153.67M-$190.11M-$130.81M -19.5%
Basic shares 53.83M53.77M53.22M47.37M +0.1%
Diluted shares 53.83M53.77M53.22M47.37M +0.1%

Options analytics

Account required
Put / call volume
0.00
Call-heavy session
Put / call open interest
—
Positioning, not flow
Max pain
7.00
-12.7% from spot
ATM implied vol
0.0%
Nearest strike to spot
Skew (10% OTM)
—
—
Call volume
16
Contracts, this expiry
Put volume
0
Contracts, this expiry
Heaviest call OI
7.00
0 contracts
Heaviest put OI
—
—

Max pain is the strike at which the largest dollar value of open contracts expires worthless. It describes current positioning; it is not a forecast and it moves as open interest changes.

Free account required

Put/call ratios, max pain, implied volatility skew and where open interest is concentrated.

Earnings

History & consensus estimates
Reported vs expected · EPS
QuarterEst.ActualSurprise
Jun 2026 -0.38-0.31 +18.4%
Mar 2026 -0.310.68 +324.0%
Dec 2025 -0.46-0.46 +0.7%
Sep 2025 -0.54-0.67 -24.7%
Forward consensus
PeriodEPSAnalystsRevenueGrowth
Current quarter -0.38 1 $9.58M +296.5%
Next quarter 0.74 1 $21.50M +102,281.8%
Current year 0.65 1 $83.16M +758.7%
Next year -1.52 1 $24.38M -70.7%

Analyst targets & ownership

Account required
Mean target$21.40
High target$36.00
Low target$8.00
Implied upside162.25%
Analyst count5
ConsensusNONE
Strong buy / Buy2 / 1
Hold2
Sell / Strong sell0 / 1
Held by insiders22.35%
Held by institutions93.91%
Institutions holding256
Free account required

Price targets, consensus spread, insider and institutional ownership.

Moving averages & technicals

Computed from 2Y daily closes
SMA 10
8.44
-3.27% from price
SMA 20
8.58
-6.52% from price
SMA 50
8.86
-9.45% from price
SMA 100
9.00
-9.36% from price
SMA 200
9.31
-13.83% from price
EMA 12
8.45
-3.49% from price
EMA 26
8.66
-5.77% from price
EMA 50
8.82
-7.53% from price
RSI (14)
38.2
Neutral
MACD (12,26,9)
-0.20
Hist -0.04
ATR (14)
0.41
5.14% of price
Realised vol 30D
43.1%
Annualised
Bollinger upper
9.21
20, 2σ
Bollinger lower
7.95
20, 2σ
50 / 200 cross
Death
8.86 vs 9.31
Trend bias
Below 200
-13.83%

Options chain

Account required
Expiry
Spot 8.16
Calls
StrikeLastBidAskVolOIIV
000.000.000.000.00000.0%
000.000.000.000.00000.0%
000.000.000.000.00000.0%
000.000.000.000.00000.0%
000.000.000.000.00000.0%
000.000.000.000.00000.0%
000.000.000.000.00000.0%
Puts
StrikeLastBidAskVolOIIV
000.000.000.000.00000.0%
000.000.000.000.00000.0%
000.000.000.000.00000.0%
000.000.000.000.00000.0%
000.000.000.000.00000.0%
000.000.000.000.00000.0%
000.000.000.000.00000.0%
Free account required

Every listed expiry, both sides of the book, with volume, open interest and implied volatility.

Risk profile

Daily returns · 1Y window
Beta vs SPY
1.01
More volatile than market
Correlation to SPY
0.28
Largely independent
Realised vol 30D
43.1%
Annualised
Market vol 1Y
13.0%
SPY, annualised
Max drawdown 1Y
-31.3%
Peak to trough
Max drawdown 5Y
-94.2%
Peak to trough
ATR 14
0.41
5.14% of price
Beta (reported)
-0.29
5Y monthly, from filing

Short interest

Semi-monthly exchange report · lags by ~2 weeks
Shares short
8.54M
Prior 8.55M
Change vs prior
-0.0%
Shorts covering
% of float
20.05%
Heavily shorted
% of shares out
16.64%
Against total outstanding
Days to cover
25.5
Crowded exit
Float
34.54M
Freely tradeable shares

Exchanges publish short interest twice a month with a settlement lag, so this is roughly two weeks behind. Days to cover divides shares short by average daily volume — it estimates how long covering would take, not whether it will happen.

Rating changes

145 on file
DateFirm ActionFromTo
May 8, 26 Citizens MAINTAINED Market Outperform Market Outperform
Feb 20, 26 RBC Capital MAINTAINED Sector Perform Sector Perform
Dec 1, 25 Citizens MAINTAINED Market Outperform Market Outperform
Nov 7, 25 HC Wainwright & Co. MAINTAINED Buy Buy
Nov 7, 25 RBC Capital MAINTAINED Sector Perform Sector Perform
Oct 28, 25 Piper Sandler MAINTAINED Overweight Overweight
Oct 7, 25 HC Wainwright & Co. MAINTAINED Buy Buy
Sep 2, 25 JMP Securities MAINTAINED Market Outperform Market Outperform
Aug 28, 25 Piper Sandler MAINTAINED Overweight Overweight
Aug 28, 25 Chardan Capital MAINTAINED Buy Buy
Aug 5, 25 RBC Capital MAINTAINED Sector Perform Sector Perform
Aug 5, 25 HC Wainwright & Co. MAINTAINED Buy Buy

Dividends & splits

Declared · from the issuer
Forward rate—
Forward yield0.00%
5-year avg yield—
Payout ratio0.00%
Ex-dividend date—
Next pay date—
Last split—
Split date—

PRIVATE STRATEGY · BY QUALIFICATION

The same data. A different seat.

The research you are reading is the input layer for a discretionary options program we run for a small number of qualified investors. Minimum $1,000,000.