The 25 most generous philanthropists in America today

Source of wealth: Transportation

Total amount donated: $100,000,000

Biggest causes: University of Notre Dame

Source: Notre Dame News

Source of wealth: Family wealth (banking)

Total amount donated: $100,000,000

Biggest causes: Art for Justice Fund, criminal justice reform, literacy organizations including Actors' Gang, the National Book Foundation, PEN America and the Pulitzer Center on Crisis Reporting

Source: Inside Philanthropy

Source of wealth: Oil

Total amount donated: $101,000,000

Biggest causes: Houston Methodist Hospital for lifesaving treatments research and the hospital's transplant center

Source: Inside Philanthropy

Source of wealth: Family wealth

Total amount donated: $105,800,000

Biggest causes: Montage Health Foundation and Northwestern University

Sources: The Chronicle of Philanthropy, Philanthropy News Digest

Source of wealth: Chemicals

Total amount donated: $110,000,000

Biggest causes: California Polytechnic State University

Source: Los Angeles Times

Source of wealth: Real estate

Total amount donated: $117,000,000

Biggest causes: University of Hawaii at Manoa Shidler College of Business and Mākālei and Lē'ahi beach parks off Diamond Head in Hawaii

Source: Honolulu Magazine

Source of wealth: Finance

Total amount donated: $140,000,000

Biggest causes: Horatio Alger Association of Distinguished Americans, Zoological Society of San Diego, National University in La Jolla, California, and Sanford Health Foundation

Source: The Chronicle of Philanthropy

Source of wealth: Law and real estate

Total amount donated: $140,024,500

Biggest causes: Wake Forest University, Queens University in Charlotte, and Wingate University

Source: The Chronicle of Philanthropy

Source of wealth: Entertainment

Total amount donated: $150,000,000

Biggest causes: David Geffen School of Medicine at UCLA, Museum of Modern Art, Licoln Center, Los Angeles County Museum of Art, St. Jude's Children's Research Hospital, and funds areas of health, education, arts and culture, LGBT and the fight against AIDS

Source: Inside Philanthropy

Source of wealth: Technology

Total amount donated: $165,000,000

Biggest causes: Nature Conservancy, Esri, donated GIS software to k-12 schools in the US

Source: Forbes

Source of wealth: Finance

Total amount donated: $177,250,000

Biggest causes: University of Illinois at Urban-Champaign, Lucile Packard Foundation, Northwestern University, Gies Foundation, Huntington Disease Society, Sarcoidosis Foundation, and Misericordia Women's League

Source: Inside Philanthropy

Source of wealth: Telecommunications

Total amount donated: $200,000,000

Biggest causes: University of California at Irvine College of Health Services, Samueli Foundation and Broadcom Foundation funding areas include: health, education, youth services, social services, Jewish community, and Southern California community

Sources: UCI News, Inside Philanthropy

Source of wealth: Family wealth

Total amount donated: $202,000,000

Biggest causes: Council of Foreign Relations, Museum of Modern Art, Mount Desert Land & Garden Preserve, Americas Society

Source: The Chronicle of Philanthropy

Source of wealth: Finance

Total amount donated: $208,200,000

Biggest causes: Open Society Foundation — democratic ideals, humanitarian efforts, economic development, education, and policy reform

Source: Inside Philanthropy

Source of wealth: Pharmaceuticals

Total amount donated: $250,000,000

Biggest causes: Columbia University Vagelos College of Physicians and Surgeons

Source: Columbia University Irving Medical Center Newsroom

Source of wealth: Technology

Total amount donated: $257,500,000

Biggest causes: Omidyar Network, Humanity United, Democracy Fund, First Look Media, and Hopelab

Source: The Chronicle of Philanthropy

Source of wealth: Energy and finance

Total amount donated: $285,000,000

Biggest causes: Laura and John Arnold Foundation — education, scientific integrity, criminal justice, and public pensions

Source: Inside Philanthropy

Source of wealth: Retail

Total amount donated: $290,000,000

Biggest causes: Holdsworth Center, The Charles Butt Foundation primarily funds grants towards education, cultural, and health institution with past grants for St. Mark's Episcopal Church, The Menil Collection, and Meadows mental Helath Policy Institute

Source: Inside Philanthropy

Source of wealth: Food and beverage

Total amount donated: $680,000,000

Biggest causes: Columbia University Herbert and Florence Irving Medical Center, New York-Presbyterian Columbia University Irving Medical Center, Metropolitan Museum of Art

Source: The Chronicle of Philanthropy

Source of wealth: Media

Total amount donated: $702,000,000

Biggest causes: Arts, education, environment, public-health groups, and programs aimed at improving city governments around the world

Source: The Chronicle of Philanthropy

Source of wealth: Investments

Total amount donated: $850,000,000

Biggest causes: Hillman Family Foundation

Source: Pittsburgh Post-Gazette

Source of wealth: Technology

Total amount donated: $1,000,000,000

Biggest causes: Michael and Susan Dell Foundation — children and family poverty in Central Texas, India, and South Africa; social enterprises and nonprofits for urban education and family economic stability

Source: Forbes

Source of wealth: Technology

Total amount donated: $2,018,944,200

Biggest causes: Chan Zuckerberg Foundation, Chan Zuckerberg Donor Advised Fund at Silicon Valley Community Foundation

Sources: The Chronicle of Philanthropy and Forbes

Source of wealth: Technology

Total amount donated: $4,780,000,000

Biggest causes: Bill & Melinda Gates Foundation — enhance healthcare, reduce extreme poverty, expand educational opportunities

Source: Forbes