Here's why the drop on high volume... What happened on friday is actually called index rebalancing. It happens every third friday of every month. This past friday was Quadruplewitching. This is a term that represents expiry of options and futures. It only happens 4 times a year, hence its name (Quad).
When a stock is added to S&P index, all indexers have to buy certain amount of shares in order to balance their S&P wieghted portfolio. On occasions that the stock price drops at the end rebalancing, It simply means that the supply over shadows the demand. The sellers obviously knew that the stock is in demand on the rebalancing day, so they purchased stocks in order to make a profit. When the number of shares sold at the end of Friday exceeded the number of shares bought, the drop happend. Index players do this on many different stocks. If you scan through the market action on that day, you will notice that many stocks suffered the same fate.
The positive news for holders here is that when the drop happens the market paticipants know that stock is oversold and the selling pressure is off. This creats a great opportunity for bargain hunters. What most people do not know is that the indexers are now even buying bigger parts of their buy orders in the following weeks. This means that with no selling pressure, and more buying on the way, the stock price should make new highs very shortly.Maybe even new 52 highs very soon.
I hope this helps!
LETSRUMBLE