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How to buy Prothena Corporation stock

Own Prothena Corporation stock in just a few minutes.

Prothena Corporation plc is a biotechnology business based in the US. Prothena Corporation shares (PRTA) are listed on the NASDAQ and all prices are listed in US Dollars. Prothena Corporation employs 66 staff and has a trailing 12-month revenue of around 0.00.

How to buy shares in Prothena Corporation

  1. Compare share trading platforms. Use our comparison table to help you find a platform that fits you.
  2. Open your brokerage account. Complete an application with your details.
  3. Confirm your payment details. Fund your account.
  4. Research the stock. Find the stock by name or ticker symbol – PRTA – and research it before deciding if it's a good investment for you.
  5. Purchase now or later. Buy your desired number of shares with a market order or use a limit order to delay your purchase until the stock reaches a desired price.
  6. Check in on your investment. Optimize your portfolio by tracking your stock.

Prothena Corporation share price

Use our graph to track the performance of PRTA stocks over time.

Prothena Corporation shares at a glance

Information last updated 2021-03-10.
52-week range$7.10 - $27.20
50-day moving average $17.87
200-day moving average $13.43
Wall St. target price$28.43
PE ratio N/A
Dividend yield N/A (0%)
Earnings per share (TTM) $-2.10

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The value of any investment can go up or down depending on news, trends and market conditions. We are not investment advisers, so do your own due diligence to understand the risks before you invest.

Is it a good time to buy Prothena Corporation stock?

The technical analysis gauge below displays real-time ratings for the timeframes you select. This is not a recommendation, however. It represents a technical analysis based on the most popular technical indicators: Moving Averages, Oscillators and Pivots. Finder might not concur and takes no responsibility.

This chart is not advice or a guarantee of success. Rather, it gauges the real-time recommendations of three popular technical indicators: moving averages, oscillators and pivots. Finder is not responsible for how your stock performs.

Is Prothena Corporation under- or over-valued?

Valuing Prothena Corporation stock is incredibly difficult, and any metric has to be viewed as part of a bigger picture of Prothena Corporation's overall performance. However, analysts commonly use some key metrics to help gauge the value of a stock.

Prothena Corporation's PEG ratio

Prothena Corporation's "price/earnings-to-growth ratio" can be calculated by dividing its P/E ratio by its growth – to give 0.8. A low ratio can be interpreted as meaning the shares offer better value, while a higher ratio can be interpreted as meaning the shares offer worse value.

The PEG ratio provides a broader view than just the P/E ratio, as it gives more insight into Prothena Corporation's future profitability. By accounting for growth, it could also help you if you're comparing the share prices of multiple high-growth companies.

Prothena Corporation financials

Revenue TTM $853,000
Gross profit TTM $-74,031,000
Return on assets TTM -18.73%
Return on equity TTM -48.65%
Profit margin 0%
Book value $4.61
Market capitalisation $888.1 million

TTM: trailing 12 months

Shorting Prothena Corporation shares

There are currently 979,672 Prothena Corporation shares held short by investors – that's known as Prothena Corporation's "short interest". This figure is 38.2% up from 709,034 last month.

There are a few different ways that this level of interest in shorting Prothena Corporation shares can be evaluated.

Prothena Corporation's "short interest ratio" (SIR)

Prothena Corporation's "short interest ratio" (SIR) is the quantity of Prothena Corporation shares currently shorted divided by the average quantity of Prothena Corporation shares traded daily (recently around 675635.86206897). Prothena Corporation's SIR currently stands at 1.45. In other words for every 100,000 Prothena Corporation shares traded daily on the market, roughly 1450 shares are currently held short.

However Prothena Corporation's short interest can also be evaluated against the total number of Prothena Corporation shares, or, against the total number of tradable Prothena Corporation shares (the shares that aren't held by "insiders" or major long-term shareholders – also known as the "float"). In this case Prothena Corporation's short interest could be expressed as 0.02% of the outstanding shares (for every 100,000 Prothena Corporation shares in existence, roughly 20 shares are currently held short) or 0.0321% of the tradable shares (for every 100,000 tradable Prothena Corporation shares, roughly 32 shares are currently held short).

Such a low SIR usually points to an optimistic outlook for the share price, with fewer people currently willing to bet against Prothena Corporation.

Find out more about how you can short Prothena Corporation stock.

Prothena Corporation share dividends

We're not expecting Prothena Corporation to pay a dividend over the next 12 months.

Prothena Corporation share price volatility

Over the last 12 months, Prothena Corporation's shares have ranged in value from as little as $7.1 up to $27.2. A popular way to gauge a stock's volatility is its "beta".

PRTA.US volatility(beta: 1.63)Avg. volatility(beta: 1.00)LowHigh

Beta is a measure of a share's volatility in relation to the market. The market (NASDAQ average) beta is 1, while Prothena Corporation's is 1.6343. This would suggest that Prothena Corporation's shares are more volatile than the average for this exchange and represent, relatively-speaking, a higher risk (but potentially also market-beating returns).

Prothena Corporation overview

Prothena Corporation plc, a clinical-stage neuroscience company, focuses on discovery and development of novel therapies for life-threatening diseases in the United States. The company is involved in developing PRX002/RG7935 that is in Phase II clinical trial for treating Parkinson's disease and other related synucleinopathies; and PRX004, an antibody that is in Phase I clinical trial for the treatment of ATTR amyloidosis. Its discovery-stage programs include Tau for treating Alzheimer's disease, progressive supranuclear palsy, frontotemporal dementia, chronic traumatic encephalopathy, and other tauopathies; Aß, or Amyloid Beta, a protein for the treatment of Alzheimer's disease; TDP-43 for amyotrophic lateral sclerosis and frontotemporal dementia; and other products for neurodegeneration. The company has a license, development, and commercialization agreement with F. Hoffmann-La Roche Ltd and Hoffmann-La Roche Inc. to develop and commercialize antibodies that target alpha-synuclein; and a collaboration agreement with Bristol-Myers Squibb to develop antibodies. Prothena Corporation plc was founded in 2012 and is based in Dublin, Ireland.

Frequently asked questions

What percentage of Prothena Corporation is owned by insiders or institutions?
Currently 0.054% of Prothena Corporation shares are held by insiders and 94.695% by institutions.
How many people work for Prothena Corporation?
Latest data suggests 66 work at Prothena Corporation.
When does the fiscal year end for Prothena Corporation?
Prothena Corporation's fiscal year ends in December.
Where is Prothena Corporation based?
Prothena Corporation's address is: 77 Sir John Rogerson?s Quay, Dublin, Ireland, 2
What is Prothena Corporation's ISIN number?
Prothena Corporation's international securities identification number is: IE00B91XRN20
What is Prothena Corporation's CUSIP number?
Prothena Corporation's Committee on Uniform Securities Identification Procedures number is: G72800108

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