Published by The Chronicle of Philanthropy, the 14th annual Philanthropy 50 list showcases the top 50 charitable donators in America. The list is based on pledges and gifts of cash and stock to nonprofit organizations.

The title of the most generous philanthropists for 2013 was awarded to the creator of Facebook, Mark Zuckerberg and his wife, Priscilla Chan. Zuckerberg and his wife gave a donation of 18 million shares of Facebook stock to a nonprofit in Silicon Valley. The 18 million shares of Facebook stock were valued at $970 million.

But there are two South Dakotans on the Philanthropy 50 list.

T. Denny Sanford is at the number 20 spot with donations totaling $130.5 million, and in the number 50 spot is the late Millicent Atkins of Ipswich, South Dakota, with donations totaling $37.5 million.

T. Denny Sanford's main beneficiary is the University of California at San Diego, but has also given gifts to the Crazy Horse Memorial Foundation and South Dakota State University.  Find out more about T. Denny Sanford's donations.

Millicent Atkins left an estimated $37.5 million to be divided equally (each receiving $12.5 million dollars) between Columbia Congregational Church UCC, Northern State University and the University of Minnesota-Twin Cities. Read Atkins' profile and find out why she chose to donate to these three different agencies.

Overall, America's big donors gave $7.7 billion to non-profit agencies in 2013, with higher education and family foundations receiving the most money.

Founder of Facebook, Mark Zuckerberg and his wife were the biggest contributors, and T. Denny Sanford and Millicent Atkins are at number 20 and 50 respectively, but read the Philanthropy 50 list to find out who else donated their share of the $7.7 billion to non-profits.

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