James Murdoch, one of the sons of billionaire media mogul Rupert Murdoch, quietly invested $ 100 million in his non-profit foundation, which then used a large chunk of the money to fund political groups during the cycle 2020 election.

CNBC discovered the enormous contribution of James Murdoch and his wife, Kathryn Murdoch, after reviewing the 2019 Group 501c3 990 tax return, which the foundation provided. The Murdochs started the foundation, called Quadrivium, in 2014.

The $ 100 million donation marks the couple’s largest known contribution to their foundation or any political effort. It happened as James and Kathryn Murdoch were building their own political operation. They have largely supported non-partisan and democratic causes. Kathryn Murdoch has previously criticized former President Donald Trump for his handling of the coronavirus pandemic.

The Murdoch family, led by Rupert Murdoch, is worth more than $ 22 billion, according to Forbes. The family controls Fox Corp. and News Corp. James’ brother Lachlan Murdoch is the CEO of Fox, which owns multiple assets, including conservative cable network Fox News.

It was previously known that James and Kathryn Murdoch had supported President Joe Biden’s 2020 campaign. But it was not known until now how much they were spending behind the scenes to have an impact on the elections. Combined with the millions they gave to campaigns and political action committees, the donation of $ 100 million would make the couple one of the top donors of the last electoral cycle.

The 2019 tax document shows that of the $ 100 million donated to the foundation, more than $ 25 million was spent on grants, especially for several political causes. The $ 25 million is also the highest amount the Murdoch couple have spent through their foundation on political causes such as tackling climate change and helping voters.

Yet, according to a person close to the family, that $ 25 million two years ago was only part of Murdoch’s massive investments throughout the 2020 election cycle. This person declined to be nominated in order to speak freely about the situation.

Since 2019, Quadrivium has donated more than $ 43 million to climate-related groups. More than $ 38 million, including $ 14 million in Quadrivium donations and $ 24 million in individual contributions from the couple, went to election organizations, including those dedicated to protecting voting rights.

The Murdoch couple also donated over $ 20 million to Biden’s campaign, groups that support and oppose Trump, and organizations dedicated to disrupting threats and extremism in line. They also made donations to groups dedicated to securing the vote in Georgia’s second round of senatorial elections in January. Democrats won both of those seats.

A spokeswoman for James and Kathryn Murdoch declined to comment.

According to the 2019 tax document, the Quadrivium Foundation had more than $ 100 million in 2020, right at the start of the primary and caucus season.

The Murdochs’ $ 100 million donation came the same year James was the CEO of 21s Century Fox before Disney bought most of the company for $ 71 billion. He was also a member of the board of directors of the family-owned News Corp. at the time.

The $ 100 million contribution to the foundation took the form of Disney shares and was concluded on the same day the Fox-Disney deal was closed. James Murdoch brought in $ 2.1 billion from the transaction.

Murdoch would later resign from News Corp’s board of directors. citing “disagreements over certain editorial content published by the company’s press organs and certain other strategic decisions”. News Corp. includes the New York Post and Dow Jones, which publishes the Wall Street Journal. Both newspapers have conservative opinion sections.

The Murdochs Foundation in 2019 donated to several organizations it had supported in the past, although nonprofits received significantly more funds that year than other groups. Quadrivium supports thematic groups that fight against climate change and try to improve access to voting.

The Murdochs’ support for voting rights groups comes as Republicans in states such as Georgia and Texas pass laws that critics say restrict people’s ability to vote. James Murdoch was one of hundreds of executives and businesses who signed a public statement opposing “any discriminatory legislation or measure which restricts or prevents any eligible voter from having an equal and fair chance to vote.”

Democracy Works Inc., a nonprofit that advertises itself as having tools to help people register to vote, has received $ 2.5 million from the Murdoch Foundation.

The education fund for Represent.Us, which claims to be non-partisan and says it works to “pass powerful state and local laws that mend our broken elections and end political corruption,” received $ 2 million of the Murdochs in 2019. The group includes a celebrity cultural advisory group including JJ Abrams, Michael Douglas and Jennifer Lawrence. The Represent.Us fund, according to its website, “has provided grants to Represent.Us to support dedicated public education and inter-party outreach activities.”

The also non-partisan Brennan Center for Justice received $ 1 million from the Murdochs two years ago. The Brennan Center has become a resource for voters and journalists to keep abreast of various bills the organization deems restrictive. The group’s website notes that state legislatures have introduced more than 380 bills in 48 states that are considered restrictive.

As for the fight against climate change, Kathryn Murdoch has been a director of the Environmental Defense Fund for years. This organization saw $ 11 million in 2019 from Quadrivium.