The Fortune 500 comes out just once a year, but the companies on it make headlines every day. Here then are today’s highlights of news and happenings coming from the biggest names in business.

By Shelley DuBois, reporter

THE AFRICAN OIL HANGUP Companies eager to start making money off of Africa’s many oil exploration resources are hitting some road blocks. Among the companies interested in African exploration is ExxonMobil (XOM) for illegally polluting the environment. Documents discovered during an invetigation allegedly highlight how Chevron’s attorney presented altered evidence to the court. [Wall Street Journal.]

JUICE WARS PepsiCo (PEP) will see Coca-Cola (KO) in court. The two drink giants are involved in a patent infringement lawsuit, set to be sorted out this coming summer. Coca-Cola says that the packaging for PepsiCo’s “Top 50” juices is too close for comfort to Coke’s juice line “Simply,” so Pepsi’s product should be banned. [Bloomberg]

NOT A SAFE BET YET Safeway (SWY) has plenty of cash, and shares are up 1.3 percent after dropping by ten percent last year. Besides, it’s been building strong brand strength in the grocery business. But it’s good performance isnt enough. Everybody wants to be a grocer these days, and Safeway is facing competition from other major discount Fortune 500 stores such was Walmart (WMT) and Target (TGT). [Los Angeles Times]

BRING IT BACK Target and Walmart along with Lowe’s (LOW) are also keeping policies in place that allow customers to return gifts even without a receipt. These holiday’s, making returns easier could differentiate competing retail outlets form one another. [Boston Globe]

SNACK CAKES AND STEAK Sara Lee (SLE) is being courted by a giant meat company–one of the largest in the world–a Brazilian company called JBS. While Sara Lee will probably seek some buyer in the near future, it turned down JBS’s initial offering price because it was too slow and low. [New York Times]