This Tech Billionaire Loads up on Ecolab (NYSE:ECL) Shares In a recent filing with the Securities and Exchange Commission (SEC), Ecolab Inc. (NYSE:ECL) revealed that Microsoft’s founder and top shareholder, Bill Gates, has bought a considerable number of shares in the company. A top shareholder is one who owns more than 10% of the company. How Much of Ecolab Did Gates Buy? In the latest transaction by Gates, the billionaire bought shares worth $19.65 million over two days. On August 17, Gates bought 66,427 shares at an average price of $174.76 per share, while on August 18, he bought 45,898 shares at an average price of $175.27 per share.