The list has 11 gifts because of ties. Eight of the donors are multibillionaires, and their combined net worth is $305.1 billion.

Topping the list is a gift from the investment guru Warren Buffett, whose net worth is estimated by Forbes at roughly $119 billion. He gave 1.5 million shares of Berkshire Hathaway Class “B” stock valued at $541.5 million to the Susan Thompson Buffett Foundation, named for his first wife, who died in 2004.

Buffett created the grantmaker in 1964 to manage the family’s charitable giving, and it remains a family affair. Two of his three children serve on its board, and it is led by his former son-in-law. The foundation primarily backs women’s reproductive health. It also provides college scholarships for students in Nebraska, where the family is from.

The donation is a special contribution that Buffett announced in November rather than one of the annual contributions he makes to the foundation and several other grant makers, which are payments toward multibillion-dollar pledges he announced in 2006.

Buffett’s gift is followed on the list by a donation from the mathematician and hedge-fund founder James Simons and his wife, Marilyn. The couple gave $500 million through their Simons Foundation to the State University of New York at Stony Brook to support the university’s endowment and to boost scholarships, professorships, research, and clinical care.

The Simons, who have an estimated net worth of $30.7 billion, have deep ties to the university. James Simons was chairman of its mathematics department from 1968 to 1978, and Marilyn Simons earned two degrees there: a bachelor’s degree in 1974 and a Ph.D. in economics in 1984. They have given the institution nearly $600 million through their foundation over the last 10 years.

Tying for third on the list is a contribution from Ross Brown, the founder of Cryogenic Industries, an industrial equipment manufacturer. In November, Brown gave the biggest gift to science in 2023 when he pledged $400 million to the California Institute of Technology. The gift will be fulfilled through his family foundation and a donor-advised fund; the money will be used to launch the Brown Institute for Basic Sciences.

The center will support scientific research at other universities and will house the Ross Brown Investigators Award Program, a fellowship program Brown started in 2020 that until this year was operated out of his foundation. The program provides five-year, $2 million awards to midcareer, tenured faculty working on chemistry and physics research.

Brown told the Chronicle in November that he no longer wanted to house the program at his foundation because he was worried about mission drift and controlling the costs of the program. A Caltech alumnus, he said the university seemed like the best fit for the fellowships.

Now that Brown has moved the program over to Caltech, university officials are in charge of awarding the $2 million grants to at least eight researchers each year. To avoid conflicts of interest, only researchers at other universities will be considered for the awards. However, Brown is directing some of this donation — about $1 million a year — toward other fundamental physical science research efforts at Caltech. There are three other donations on the list that support scientific research.

Nike cofounder Phil Knight and his wife, Penny, made a $400 million pledge to the 1803 Fund. The commitment from the Knights, whose net worth is pegged at $43 billion, will establish Rebuild Albina, an effort to revive the economic and cultural prosperity of Albina, a historic area of Portland, Oregon, that was once a thriving Black neighborhood but fell into neglect in the 1970s.

Black families in Albina were displaced by a ruinous mix of predatory lending, discriminatory government practices, and huge, long-term construction projects that shuttered businesses and destroyed the neighborhood. It was a pattern that played out in many U.S. cities during that era. Rebuild Albina officials plan to renovate the area, pay for education programs and education-related services for children and their families, and support a range of projects meant to deepen the area’s cultural roots. The Knights are giving the money both personally and through their Knight Foundation.

Daniel and Jennifer Gilbert gave $375 million through their Gilbert Family Foundation to Henry Ford Health to build two medical centers to take the fourth spot on the list. Dan Gilbert founded Rocket Mortgage and is chairman of the Cleveland Cavaliers. The couple’s net worth is estimated at nearly $29 billion.

One of the medical centers will be a rehabilitation center at the Henry Ford Hospital in Detroit. The center will serve patients recovering from spinal-cord injuries, stroke, traumatic brain injuries, and other conditions. The Gilberts directed $10 million of the total to create a special fund to pay for rehabilitation care for low-income Detroit residents who have little or no health insurance coverage.

The other medical center, the Nick Gilbert Neurofibromatosis Research Institute, will bring medical professionals and researchers from Henry Ford Health and Michigan State University Health Sciences together to seek a cure for neurofibromatosis, a genetic disorder that causes tumors to grow on nerve pathways throughout the body. Nick Gilbert, the donors’ oldest son, was diagnosed with the disease as a child and devoted much of his life to raising awareness about it. He died in May at age 26.

Coming in at No. 5 is a gift from financier Kenneth Griffin, who gave $300 million through his Kenneth C. Griffin Charitable Fund to back financial aid and a range of other programs within Harvard’s Faculty of Arts and Sciences. Griffin, whose net worth is estimated at roughly $38 billion, has given extensively to his alma mater over the years, including tens of millions of dollars for financial aid for undergraduates.

Griffin made another gift that was among the biggest of 2023. He partnered with the entertainment executive David Geffen to provide $400 million to Memorial Sloan Kettering Cancer Center. Neither philanthropist would disclose the precise amount he gave through his grantmaker so the Chronicle didn’t count those contributions in its rankings.

The Chronicle’s annual rankings are based on the 10 biggest publicly announced gifts. The tally does not include contributions of artwork or gifts from anonymous donors. In March, the Chronicle will unveil its annual ranking of the 50 biggest donors, a list based on philanthropists’ total contributions in 2023 rather than individual gifts.