The Science Philanthropy Alliance is a coalition of science advocacy groups and foundations. It is a project of the left-of-center New Venture Fund, which employs the employees of the Alliance. New Venture Fund is a part of the Arabella Advisors network of liberal advocacy projects, which critics call “dark money.” 
The goal of the Science Philanthropy Alliance is to fund “basic science” research. To do this, it directs the donations of billionaires, millionaires, and foundations.
The Science Philanthropy Alliance is an umbrella organization of various donor organizations that support “basic science” research. Basic science research is the study of more fundamental elements of science that are then applied to more advanced research. 
The Alliance is a project of the left-of-center advocacy group New Venture Fund. The New Venture Fund has been called a “dark money” fund that allows left-wing activists and funders to fund causes anonymously. Money donated to the New Venture Fund is used to attack conservative and Republican causes and is used to promote left-wing causes. 
Since the Science Philanthropy Alliance is not a standalone organization with its own tax-exempt status, donations are directed through the New Venture Fund. 
Marc Kastner is the president of the Science Philanthropy Aliance. Previously, he held various positions at the Massachusetts Institute of Technology. 
Kastner is also a fellow at the American Association for the Advancement of Science (AAAS), a science advocacy organization that supports a number of left-of-center policies. During the Cold War, AAAS had a history of advocating for population control measures. 
Kastner is an employee of the New Venture Fund. His salary in 2016 was $531,250, which made him the highest paid employee of the New Venture Fund. 
Valerie Conn is the executive director of the Alliance. She was the Alliance’s second employee and originally joined as a vice president in 2015. Previously, she was vice president for strategy at the B612 Foundation, working there from 2014-15. Before that, she was a development officer at the University of Chicago. 
Like Kastner, Conn is technically an employee of the New Venture Fund. Conn made $296,179 in 2016 which made her the third-highest paid employee at the New Venture Fund. 
The chairman of the board of directors is Robert W. Conn. Conn is the president and CEO of The Kavli Foundation. 
In 2015, six foundations—the Gordon and Betty Moore Foundation, the Kavli Foundation, the Simons Foundation, the Sloan Foundation, the Howard Hughes Medical Institute, and the Research Corporation for Science Advancement—created the Science Philanthropy Alliance. The Alliance hired Marc Kastner, who was then serving as an administrator at MIT and had been nominated by President Barack Obama to lead the Department of Energy’s Office of Science. Kastner’s nomination was not voted on by the U.S. Senate. 
The Alliance was formed in response to reductions in federal funding for “basic science” research that were implemented in 2012. It set a goal of donating $1 billion a year over the next five years.