NEW YORK ( TheStreet) -- These stocks go ex-dividend Thursday, meaning an investor must purchase the shares Wednesday to qualify for the next dividend payment: Tanger Factory Outlet Centers ( SKT), Unum ( UNM) and Mesabi Trust ( MSB). These three stocks received buy ratings from TheStreet Ratings. Tanger Factory Outlet Center Tanger is an outlet shopping real estate investment trust. Hilliard Lyons analysts lowered their rating of Tanger on Dec. 20 to neutral from long-term buy based on stock price appreciation. "We believe outlet centers will be the main area of retail development over the next few years," Hilliard Lyons analysts wrote. "Given a pullback in stock price and no change in fundamentals, we would look to raise our rating on the shares." Tanger shares have slipped less than 0.5% year to date. The stock rose about 14.5% in 2011. Forward Annual Dividend Yield: 2.8% Rated "B (Buy)" by TheStreet Ratings: The company's third-quarter gross profit margin decreased from a year ago. In the third quarter, stockholders' net worth increased 4.07% from the previous year. The Street Ratings' price target on Tanger is $33.43. Shares closed Tuesday at $29.20.