The donation will finance 20 full-ride scholarships in each of the next three years -- the largest scholarship initiative in the law school's history. The merit scholarships will cover one in 10 of the students enrolled in the law school.
"David's magnificent act of philanthropy is a game-changer," law dean Michael Schill said in a written statement on Wednesday announcing the gift. "Our faculty are dedicated to teaching the nation's best law students, a commitment that has created the law school's interactive, intellectual atmosphere. By helping our students, we will enhance this distinctive academic culture."
Rubenstein, a major player on the private-equity scene, graduated from the law school in 1973. He attended on a full-tuition scholarship.
"My scholarship meant that I could tell my parents I wouldn't need any money from them for law school," he said. "That meant a lot to me."
Rubenstein is one of 40 billionaires who in August signed the "Giving Pledge," a commitment to donate the majority of their wealth to charity. The initiative is spearheaded by Warren Buffett and Bill and Melinda Gates.
In his pledge letter, Rubenstein described his blue-collar upbringing in Baltimore, when making a lot of money was not his focus.
"My goal was simply to do well enough in school to secure scholarships to college and law school to practice law; and to fulfill a long-time desire -- perhaps inspired by President Kennedy's inaugural address -- to move back and forth from the practice of law into various public service positions," Rubenstein wrote.
Rubenstein worked at Paul, Weiss, Rifkind, Wharton & Garrison for three years after graduating from law school, then became a deputy domestic policy assistant in the Carter administration. He helped found the Carlyle Group, one of the largest private equity firms in the world, in 1987. Forbes magazine has estimated his net worth at $2.5 billion -- making him the 374th richest person in the world.
In the scholarship announcement, Rubenstein said he hopes his gift will prompt other law school alumni to donate.
"The law school gave m so much, and I wanted to give back," he said.