Mr. Lewis is chief executive of Grand Circle Corporation, a Boston company that specializes in cruises and other trips abroad. Mr. Lewis, 63, gave $29.4-million to the Boston Foundation to establish a donor-advised fund. The money came from a 40-percent stake in a luxury cruise ship operating in French Polynesia that Mr. Lewis offered the foundation in 2007. At the time, the ship was valued at about $100-million. Mr. Lewis owned a 50-percent stake, and his brother, Henry R. (Hank) Lewis, owned the other half. Since the two were in the process of selling the luxury vessel, foundation officials decided to accept Alan Lewis’s offer, assuming that the sale would go through and, after liquidating the shares, the foundation would receive roughly $40-million. Shortly after Mr. Lewis offered the foundation a 40-percent share in the ship, in 2007, Hank Lewis promised the foundation an additional 3-percent stake. But when the financial crisis hit in 2008, it became impossible to sell a high-end cruise ship. This put the foundation at risk since it faced heavy tax penalties if it held onto its shares for more than five years. Around this time, a complicated financial feud over the ship and the donation broke out between the two brothers. The rift forced Alan Lewis and the Boston Foundation to enter together into arbitration against Hank Lewis. In 2011, a judge ruled in favor of Alan Lewis and the foundation, making it possible for the foundation to receive the money. The shares Alan Lewis gave to the foundation ultimately resulted in the $29.4-million donation. His fund will primarily support causes in and around Boston but may benefit charities in other places as well. The shares Hank Lewis gave the foundation amounted to about $2.2-million. He has also directed his donation to establish a donor-advised fund.