Stock Quotes in this Article: ARIA, PFE, ZTS, SGNT

MADISON, Wis. (Stockpickr) -- Professional traders running mutual funds and hedge funds don't just look at a stock's price moves; they also track big changes in volume activity. Often when above-average volume moves into an equity, it precedes a large spike in volatility.

Major moves in volume can signal unusual activity, such as insider buying or selling -- or buying or selling by "superinvestors."

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Unusual volume can also be a major signal that hedge funds and momentum traders are piling into a stock ahead of a catalyst. These types of traders like to get in well before a large spike, so it's always a smart move to monitor unusual volume. That said, remember to combine trend and price action with unusual volume. Put them all together to help you decipher the next big trend for any stock.

With that in mind, let's take a look at several stocks rising on unusual volume today.

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Zoetis

Zoetis (ZTS) discovers, develops, manufactures and commercializes animal health medicines and vaccines for both livestock and companion animals. This stock closed up 1.5% at $33.55 on Wednesday.

Wednesday's Volume: 21.56 million

Average Volume: 1.61 million

Volume % Change: 522%

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From a technical perspective, ZTS spiked higher here back above its 50-day moving average of $32.94 with heavy upside volume. This move is quickly pushing shares of ZTS within range of triggering a major breakout trade. That trade will hit if ZTS manages to take out some near-term overhead resistance levels at $34 to $34.74 and then once it clears its all-time high of $35.42 with high volume.

Traders should now look for long-biased trades in ZTS as long as it's trending above its 50-day at $32.94 or above $32 and then once it sustains a move or close above those breakout levels with volume that hits near or above 1.61 million shares. If that breakout triggers soon, then ZTS will set up to enter new all-time high territory, which is bullish technical price action. Some possible upside targets off that breakout are $40 to $43.

Pfizer

Pfizer (PFE) is a research-based biopharmaceutical company. This stock closed up 1.8% at $29.30 on Wednesday.

Wednesday's Volume: 78.58 million

Average Volume: 32.68 million

Volume % Change: 131%

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From a technical perspective, PFE gapped higher here back above its 50-day moving average of $29.11 with heavy upside volume. This move briefly pushed PFE into breakout territory, since it took out some near-term overhead resistance at $29.69. Shares of PFE closed below that breakout level to $29.30 and volume was well above its three-month average action of 32.58 million shares. This move has PFE trending within range of triggering a major breakout trade. That trade will hit if PFE manages to take out Wednesday's high of $30.04 and then once it clears more resistance at $30.33 to $30.89 with high volume.

Traders should now look for long-biased trades in PFE as long as it's trending above its 50-day at $29.11 and then once it sustains a move or close above those breakout levels with volume that hits near or above 32.68 million shares. If that breakout triggers soon, then PFE will set up to re-test or possibly take out its next major overhead resistance levels at $32.50 to around $35.

Sagent Pharmaceuticals

Sagent Pharmaceuticals (SGNT) is a pharmaceutical company that develops and sources products that the company sells primarily in the U.S. This stock closed up 3.7% at $17.95 on Wednesday.

Wednesday's Volume: 236,000

Average Volume: 56,045

Volume % Change: 284%

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From a technical perspective, SGNT ripped higher here right above its 50-day moving average of $17.13 with above-average volume. This stock recently formed a double bottom chart pattern at $15.76 to $15.71 and then surged higher back above its 50-day with strong upside volume flows. That move is quickly pushing shares of SGNT within range of triggering a near-term breakout trade. That trade will hit if SGNT takes out Wednesday's high of $18.36 to $18.67 with high volume.

Traders should now look for long-biased trades in SGNT as long as it's trending above Wednesday's low of $17.31 or above its 50-day at $17.13 and then once it sustains a move or close above those breakout levels with volume that hits near or above 56,045 shares. If that breakout triggers soon, then SGNT will set up to re-test or possibly take out its next major overhead resistance levels at $20 to $22.

Ariad Pharmaceuticals

Ariad Pharmaceuticals (ARIA) is engaged in the discovery and development of breakthrough medicines to treat cancers by regulating cell signaling with small molecules. This stock closed up 5.1% at $18.43 on Wednesday.

Wednesday's Volume: 8.15 million

Average Volume: 2.99 million

Volume % Change: 157%

From a technical perspective, ARIA spiked higher here back above its 50-day moving average at $18.16 with heavy upside volume. This move briefly pushed shares of ARIA into breakout territory, since the stock flirted with some near-term overhead resistance levels at $18.33 to $18.63 and at $19.21. Shares of ARIA pulled back and closed below the latter of those breakout levels, but volume was well above its three-month average action of 2.99 million shares. This move now has ARIA trending within range of triggering a near-term breakout trade. That trade will hit if ARIA manages to take out Wednesday's high at $19.64 and then its 200-day moving average at $20.53 with high volume.

Traders should now look for long-biased trades in ARIA as long as it's trending above its 50-day at $18.16 or above Wednesday's low of $17.60 and then once it sustains a move or close above those breakout levels with volume that hits near or above 2.99 million shares. If that breakout triggers soon, then ARIA will set up to re-test or possibly take out its next major overhead resistance levels at $22.50 to $24.50.

To see more stocks rising on unusual volume, check out the Stocks Rising on Unusual Volume portfolio on Stockpickr.

-- Written by Roberto Pedone in Madison, Wis.

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At the time of publication, author had no positions in stocks mentioned.

Roberto Pedone, based out of Madison, Wis., is an independent trader who focuses on technical analysis for small- and large-cap stocks, options, futures, commodities and currencies. Roberto studied international business at the Milwaukee School of Engineering, and he spent a year overseas studying business in Lubeck, Germany. His work has appeared on financial outlets including CNBC.com and Forbes.com. You can follow Pedone on Twitter at www.twitter.com/zerosum24 or @zerosum24.