What: Shares of LPL Financial Holdings (LPLA 0.57%) are surging by 14% as of 11 a.m. EST.

So what: How quickly fortunes change. After plunging more than 35% intraday on Friday due to disappointing earnings results, shares of LPL Financial are back on the list of market movers -- this time in a positive direction.

The stock appears to be responding to two analyst upgrades. An analyst at Credit Suisse upgraded the company to "outperform" from "neutral," but cut his price target to $16.50 per share, down from a previous target of $28. Previously, Credit Suisse reiterated its neutral rating on the Friday, the day of its earnings release.

Separately, an analyst from Morgan Stanley upgraded the company to "overweight" from "equal weight."

Now what: LPL Financial will undoubtedly remain one of the most volatile stocks on Wall Street. The company has used its borrowing capacity to repurchase shares, slashing its diluted share count from 108 million shares to 95.3 million since the second quarter of 2013. Though repurchases helped drive shares higher, LPL Financial is highly leveraged.

The company noted that its leverage ratio (as calculated per its debt agreements) stands at 3.8 times an adjusted measure of earnings versus its covenant requirements that hold it to no more than five times leverage. On the balance sheet, note that it is currently levered at about 5.3 times debt to equity.

High financial leverage ensures that even the smallest fluctuations in the company's enterprise value result in huge shifts in the equity value, making for a very volatile stock, indeed.