The Climate Science Legal Defense Fund (CSLDF) in a not-for-profit organization established in 2011 to provide legal assistance to researchers and institutions engaged in climate science facing legal challenges from private entities such as think tanks and legal foundations. In 2012, CSLDF formally affiliated with Public Employees for Environmental Responsibility, a nonprofit providing aid and advice to government whistleblowers and scientists working on environmental issues. CSLDF is funded entirely through private donations. As of January 2011, CSLDF has received $25,000 in donations.