The California State Teachers’ Retirement System (CalSTRS) this week filed a lawsuit against current and former Walmart executives stemming from the April 22 New York Times article, which chronicled the company’s alleged use of bribes to accelerate expansion in Mexico and efforts by top executives to quash an investigation when the situation was called to their attention.

April same-store sales at Target increased 1.1% and helped the company achieve a 5.3% first-quarter comps increase that was the highest in six years. How much of the performance was due to record warm weather versus good execution of a solid strategy against the back drop of an improved economy is debatable.

First quarter sales at Amazon.com surged 34% to $13.2 billion during the first quarter ended March 31, but profits declined 35% to $130 million due to rising expenses related to growth initiatives.

Landfill operators got some bad news this week when Walmart said it prevented 81% of waste generated by U.S. stores from going to landfills. That nugget is just one example of the progress Walmart has made on its broad sustainability agenda and was among numerous others contained in the company’s 5th annual Global Responsibility Report released this week.