The first time Edward A. Snyder, dean of the University of Chicago's graduate business school, asked David G. Booth to donate money to name something on the campus, Mr. Booth said no. Five years later, the University's Graduate School of Business is named the University of Chicago Booth School of Business, after Mr. Booth gave what is valued as a $300-million gift to the school in the form of an income stream and equity interest from shares in his company, as well as outright cash. It was the largest gift in the university's history and the biggest gift ever given to a business school. Mr. Booth, who founded the investment firm Dimensional Fund Advisors after graduating from Chicago with an M.B.A. in 1971, was strongly interested in giving back to the school that gave him the ideas on markets and investing that he used to build his company. Eugene Fama, a professor at the school and his mentor, got him his first job. Faculty members served on his company's board. When Dean Snyder asked him for a big gift years ago, it wasn't possible for him at the time. But as his firm grew, he felt the time was right to commit as large an amount as he could to the school.