5 of Last Week's Biggest Winners

What's better than momentum? Mo' momentum. Let's take a closer look at five of this past week's biggest scorchers.

Source: Barron's.

YY spiked after Citi and Morgan Stanley initiated coverage of the Chinese online gaming and communications speedster with bullish ratings. It's been three months since YY went public, so it's only natural to see underwriters offer up rosy perspectives at this point.

J.C. Penney moved higher after the legal tussle with a rival retailer to sell Martha Stewart merchandise intensified. Shares of the struggling retailer also moved higher on Friday after a New York Post report claimed that the chain will lay off at least 300 -- or 10% -- of its headquarters workforce. This isn't good news, naturally, but investors see this as CEO Ron Johnson's belt-tightening ahead of a possible turnaround.

Celldex Therapeutics also had a winning week. The young biotech continues to gain steam after revealing positive results for its solution for hematopoietic stem cell transplantation. It's important to note that this is just the first phase of trials. Biotech watchers know that we have a long way to go here. However, Celldex does have other treatments in its pipeline.

Magnum Hunter moved higher after its CEO appeared on CNBC's Mad Money. He told Jim Cramer the oil and gas company is having a lot of success with its recently acquired assets in North Dakota.

Radian investors discovered that the house always wins. Shares of the mortgage insurance provider rose after a Susquehanna analyst upgraded the company. The analyst's $14 price target would represent nearly a doubling of the stock from here. As home prices start to firm up, the risks of providing mortgage insurance diminish.

Keep the good vibes coming
You nailed some of last week's winners. Now let's see you keep going.