Entrepreneurs are more likely to make charitable contributions than any other type of professional in the U.S. According to a report released by Ernst & Young, personal passion and corporate philanthropy go hand in hand. After surveying more than 160 CEOs and company founders, the study found that 89 percent of respondents donate money (both via their companies and personally) and an additional 70 percent donate their time, too.

In fact, many entrepreneurs make donations that average twice the size of those of major corporations. These entrepreneurs write charitable giving into their business plans, and 29 percent specifically seek out organizations with goals and missions that complement their own businesses. Thousands of business owners give back each year. Here are seven admirable leaders who donated among the highest amounts.

1. David Murdock

Founder of the Dole Food Company and owner of Castle & Cooke, Murdock donated $50 million to the David H. Murdock Research Institute in 2013. At 90 years of age, Murdock continues to support his charitable branch, which researches human health, nutrition, and agriculture at the North Carolina Research Campus.

2. Buerger Family

The Buerger Family founded Coventry, a Pennsylvania life insurance company, and are multi-generational philanthropists. In 2013, they donated $50 million to the Children's Hospital of Philadelphia's Center for Advanced Pediatric Care. Reid Buerger, the son of the original founder, serves as a hospital trustee.

3. Robert and Anne Bass

The Basses donated $50 million to Duke University in 2013. He's founder of Aerion Corporation in Reno, Nevada, and president of Keystone Group, and she has served on Duke's board of directors for 10 years. Their gift will create Bass Connections, a campaign to support collaboration and interdisciplinary studies at Duke.

4. Abraham Mitchell

Donating just over $50 million to the University of South Alabama, Mitchell co-founded the Mitchell Group, a thriving Alabama real estate firm. He's asked that $25 million go to academic scholarship endowment and the other half to the Mitchell College of Business. Surprisingly, Mitchell, age 79, never went to the university, but had a strong friendship with a former president of the campus, Gordon Moulton.

5. Arthur and Rebecca Samburg

The couple donated more than $50 million to the New York Presbyterian Hospital and Columbia Business School in 2013. Founder of Pequot Capital Management, a hedge fund company, Arthur Samberg has always had a hugely charitable side. Columbia is his alma mater and he's currently on the board of overseers.

6. Dale and Sarah Ann Fowler

Pledging $55.1 million to Chapman University Dale E. Fowler School of Law in Orange, California, the couple says it's due to Mr. Fowler's having a minimal relationship with his alma mater in the 1980s. He's the founder of Fowler Properties, a highly successful California real estate development business. Since the 1990s, he's grown closer to his roots and now serves on the board of trustees at the university.

7.) James Clark

As co-founder of Netscape, Clark often tops the charts when it comes to philanthropy. He donated $60 million in 2013 to Stanford University's James H. Clark Center for Biomedical Engineering and Sciences. He was also one of the founders of this department in 1999 and gave it a previous gift of $90 million. However, this latest round will go toward solely research.