Prothena Corporation plc Insider Trading

PRTA

Last 12 months

Insiders sold 136K and bought nothing on the open market.

All of the selling was scheduled in advance under 10b5-1 plans. The last open-market buy by an executive or director was in Mar 2017.

Net open-market

−136K

0 buys · 2 sales

Under a 10b5-1 plan

100%

of the value sold

Insiders who bought / sold

0 / 2

executives and directors

Last open-market buy

Mar 2017

Mar 9, 2017

Get an email when PRTA's executives or directors buy, or make a large sale outside a plan.

Trades · last 2 years

Date	Insider	Trade	Shares	Price	Value	Of their stake	Filing
Oct 22 – 23	William P Scully Large holder	Bought 2 parts	150,000	$8.15 average	$1.22M	8.6%	Form 4
Oct 13 – 14	William P Scully Large holder	Bought 2 parts	110,000	$8.36 average	920K	6.7%	Form 4
Oct 7 – 8	William P Scully Large holder	Bought 2 parts	215,000	$8.47 average	$1.82M	15%	Form 4
Oct 2	William P Scully Large holder	Bought	100,000	$8.57	857K	7.5%	Form 4
Sep 29	William P Scully Large holder	Bought	162,000	$8.68	$1.41M	14%	Form 4
Sep 28	William P Scully Large holder	Bought	103,500	$8.60	890K	9.7%	Form 4
Sep 18	William P Scully Large holder	Bought	100,000	$8.43	843K	10%	Form 4
Sep 2	William P Scully Large holder	Bought	27,000	$9.47	256K	2.9%	Form 4
Aug 20	William P Scully Large holder	Bought	50,000	$8.79	440K	5.6%	Form 4
Aug 7	William P Scully Large holder	Bought 2 parts	37,500	$8.62 average	323K	4.2%	Form 4
Jul 29	Anne Evans Kingston Chief Strategy Officer	Sold10b5-1 plan	7,662	$8.47	65K	12%	Form 4
Jul 29	Michael John Isaacs General Counsel & Company Sec.	Sold10b5-1 plan	8,386	$8.47	71K	19%	Form 4
Jun 16	William P Scully Large holder	Bought	20,000	$7.90	158K	2.3%	Form 4
Jun 11	William P Scully Large holder	Bought	125,000	$8.17	$1.02M	12%	Form 4
Jun 4	William P Scully Large holder	Bought	50,000	$9.31	466K	4.9%	Form 4
Jun 2	William P Scully Large holder	Bought	50,000	$9.43	472K	5.2%	Form 4
May 22	William P Scully Large holder	Bought	100,000	$9.81	981K	12%	Form 4
May 2, 2025 – May 6, 2025	Ecor1 Capital, LLC Large holder	SoldNo plan 3 parts	6,279,684	$8.09 average	$50.8M	54%	Form 4
Dec 18, 2024 – Jan 14, 2025	William P Scully Large holder	Bought 6 parts	207,436	$13.26 average	$2.75M	29%	Form 4

Oct 22 – 23
William P Scully
Large holder · bought 150,000 at avg $8.15
$1.22M
8.6% of stake
Oct 13 – 14
William P Scully
Large holder · bought 110,000 at avg $8.36
920K
6.7% of stake
Oct 7 – 8
William P Scully
Large holder · bought 215,000 at avg $8.47
$1.82M
15% of stake
Oct 2
William P Scully
Large holder · bought 100,000 at $8.57
857K
7.5% of stake
Sep 29
William P Scully
Large holder · bought 162,000 at $8.68
$1.41M
14% of stake
Sep 28
William P Scully
Large holder · bought 103,500 at $8.60
890K
9.7% of stake
Sep 18
William P Scully
Large holder · bought 100,000 at $8.43
843K
10% of stake
Sep 2
William P Scully
Large holder · bought 27,000 at $9.47
256K
2.9% of stake
Aug 20
William P Scully
Large holder · bought 50,000 at $8.79
440K
5.6% of stake
Aug 7
William P Scully
Large holder · bought 37,500 at avg $8.62
323K
4.2% of stake
Jul 2910b5-1 plan
Anne Evans Kingston
Chief Strategy Officer · sold 7,662 at $8.47
65K
12% of stake
Jul 2910b5-1 plan
Michael John Isaacs
General Counsel & Company Sec. · sold 8,386 at $8.47
71K
19% of stake
Jun 16
William P Scully
Large holder · bought 20,000 at $7.90
158K
2.3% of stake
Jun 11
William P Scully
Large holder · bought 125,000 at $8.17
$1.02M
12% of stake
Jun 4
William P Scully
Large holder · bought 50,000 at $9.31
466K
4.9% of stake
Jun 2
William P Scully
Large holder · bought 50,000 at $9.43
472K
5.2% of stake
May 22
William P Scully
Large holder · bought 100,000 at $9.81
981K
12% of stake
May 2, 2025 – May 6, 2025No plan
Ecor1 Capital, LLC
Large holder · sold 6,279,684 at avg $8.09
$50.8M
54% of stake
Dec 18, 2024 – Jan 14, 2025
William P Scully
Large holder · bought 207,436 at avg $13.26
$2.75M
29% of stake

How to read this. Insiders sell for many reasons: taxes, diversifying, a house. Open-market buys are rarer and say more. A 10b5-1 plan is a trading schedule set up months in advance, so those sales were not timed on news. Large holders (funds and 10% owners) are listed under Everything but not counted as insiders. If you own or watch PRTA, we send a push when an executive buys or makes a large sale outside a plan.

Source: SEC Form 4 filings, filed within two business days of each trade and checked for new ones every hour.

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Held by ETFs

PRTA is in 15 US ETFs. The largest of them, with PRTA's weight in each:

Spot a number that looks wrong? Check it in PRTA's SEC filings or

Download this analysis as a PDF (Pro)

Data sourced from SEC EDGAR filings and third-party price providers. Scores, valuations, and metrics are algorithmic estimates. This is not investment advice. See our Terms and Methodology.

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