WINDERMERE, Fla. ( 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.>>5 "Magic Formula" Stocks for 2013 Major moves in volume can signal unusual activity, such as insider buying or selling -- or buying or selling by "superinvestors." 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. >>5 Stocks Insiders are Stashing McGraw-Hill Companies ( MHP) This is a global information services provider serving the education, financial services and business information markets with a range of information products and services. This stock is trading up 3.3% at $56.08 in recent trading. Today's Volume: 4.77 million Average Volume: 1.87 million Volume % Change: 313% Shares of MHP are spiking higher today after the company declared a special dividend of $2.50 per share on Dec. 27 to shareholders of record on Dec. 18. From a technical perspective, MHP is bouncing higher here right above its 50-day moving average of $53.51 with monster upside volume. This move is quickly pushing the stock within range of triggering a major breakout trade. That trade will hit once MHP takes out its 52-week high at $56.75 with high volume. Traders should now look for long-biased trades in MHP as long as it's trending above today's low of $54.52, and then once it sustains a move or close above its 52-weeek high with volume that hits near or above 1.87 million shares. If that breakout triggers soon, then MHP will enter new 52-week high territory, which is bullish technical price action. Some possible upside targets are $60 to $65 in the near future.