(Read More: See the Day's Top Percentage Winners & Losers)
Citigroup - Citi has been upgraded to "buy" from "neutral" at UBS, thanks to better efficiency and waning earnings headwinds from the Citi Holdings unit.
Best Buy - Piper Jaffray has upgraded the electronics retailer's shares to "overweight" from "neutral," saying new management is in the very early stages of a multi-year turnaround process.
Sony - Chairman Howard Stringer will retire from the company at its annual shareholder meeting in June. Stringer became chief executive of Sony in 2005, then stepped down from that role last April to serve solely as chairman.
Electronic Arts - EA has issued an apology for problems plaguing the launch of its latest "SimCity" game. Technical problems with servers shut many gamers out of the system for several days, which EA blames on server instability.
Walt Disney - Disney's "Oz the Great and the Powerful" earned $80.3 million in North American ticket sales during its debut weekend, giving it the number one spot at the weekend box office.
Several drug and medical device makers are in the news this morning:
Gilead Sciences - Gilead says its heart drug Ranex reduced chest pain in patients with diabetes, according to a clinical trial. This was the first test of the drug specifically in diabetic patients.
Abbott Laboratories - Abbott could see some negative fallout after a drug-coated heart stent from a Japanese company proved as effective as Abbott's top-selling stent known as Xience.
Edwards Lifesciences - Edwards saw a redesigned version of its heart valve replacement system Sapien perform well in a new clinical study.
Boston Scientific - The company said its atrial fibrillation device known as Watchman proved safe in a clinical study.
Other stocks to watch:
Amazon.com - Amazon is reportedly being challenged by publishing industry groups in its effort to own new Internet domains such as .book, .author, and .read, according to The Wall Street Journal. It said the groups feel that allowing Amazon to own those names would be a threat to competition.
Bed Bath & Beyond - Bed Bath could see its stock rise 25 percent over the next year based on the retailer's performance, but could fetch a 43 percent premium in a buyout, according to an article in Barron's. The paper said there's no indication that Bed Bath is looking to sell itself.
Goldman Sachs - Goldman has lost its effort to turn aside a vote on splitting the chairman and CEO roles, according to correspondence posted on the U.S. Securities and Exchange Commission website. A letter sent to Goldman by SEC counsel says the agency cannot concur with Goldman's view that the shareholder proposal does not warrant a vote.
Kraft Foods Group - The stock will be joining the Nasdaq 100 index next week, replacing Starz. Kraft compromises the North American grocery business of the old Kraft Foods, which was renamed Mondelez after spinning off the grocery unit.