Wal-Mart Stores confirmed that it is investigating its operations in Mexico for possible violations of the U.S. law that prohibits bribery overseas.

Walmart’s U.S. stores regained customer traffic during the fourth quarter and president and CEO Mike Duke said the company had a great Christmas, but it didn’t feel that way to investors who couldn’t dump shares of the company fast enough after earnings were released on Tuesday.

Although Walmart won’t provide official fourth-quarter sales guidance until Nov. 15 when it releases third-quarter sales, company executives sounded very bullish about Walmart’s prospects for holiday success and longer-term growth during an all-day meeting with financial analysts on Wednesday.

Wal-Mart Stores is in search of a new head of its global ecommerce and global sourcing businesses now that Eduardo Castro-Wright announced his retirement effective July 1, 2012.

Wal-Mart Stores president and CEO Mike Duke was on Capitol Hill this week making the case for modernizing the U.S. tax code even as Democratic and Republican lawmakers continued to engage in brinksmanship over what all agree is a disturbing level of national indebtedness. Duke testified before the United States Senate Committee on Finance, which was holding hearings on CEO perspectives on how the tax code affects hiring, businesses and economic growth. A transcript of his prepared remarks appears below:

Walmart said it will donate $20 million to the Crystal Bridges Museum of American Art to provide for free admission for the next five years. The expansive world class facility scheduled to open Nov. 11 in Bentonville, Ark. was founded by the Walton Family Foundation in 2005.

It is logical that Wal-Mart Stores Inc. president and CEO Mike Duke would top Supermarket News’ Power 50 list of the food industry’s most influential executives. The company sells more food, by a large margin, than anyone else, therefore a case could be made that Duke, or whoever is CEO of Walmart, should top the publication’s list each year.

After nearly four hours of music, cheering, celebrity appearances and brief presentations by senior executives, Wal-Mart Stores president and CEO Mike Duke wrapped up the company’s annual shareholders’ extravaganza Friday morning by sharing five priorities associated with serving what he called the next generation of customers.

Despite progress on several key merchandising initiatives during the first quarter, it wasn’t enough to prevent Walmart from logging a 1.1% decline in same-store sales, losing customer traffic and introducing the possibility the second quarter will bring more of the same. The company’s forecast for second quarter same-store sales envisions a range of possibilities between a 1% decline and 1% increase.

Walmart turned what appeared to be some fairly grim news on the U.S. sales front into a message of inspiration by pointing out that growing comps is the senior management’s highest priority, and positive results are being realized in areas where strategic initiatives have been in place the longest.

Wal-Mart Stores CEO Mike Duke said rising gas prices are hurting the chain’s main customers, who are having an even harder time stretching their dollars to the next payday than they did a year ago.

Mike Duke presented at the Barclay’s conference Tuesday, and, as we predicted in last week’s WNN, he did not speak about first-quarter sales, which the company will report on May 17. Instead Duke focused on such broad goals as growth, leverage, but offered little detail on how the company plans to achieve them.

According to Duke, a main priority for Walmart is growth, particularly at its U.S. stores. This is not surprising since the company has been reporting negative comps for its Walmart U.S. business for the past few quarters. In order to achieve positive comps, Duke said, stores need to offer the right assortment.