Robert Mercer, billionaire co-CEO of the $50 billion Renaissance Technologies hedge fund group, is stepping down from its leadership and selling his ownership stake in Steve Bannon's Breitbart website to Mercer's daughter Rebekah, according to a letter Mercer sent Renaissance partners and staff Wednesday.

In the letter, Mercer affirmed his support for Bannon and conservative politics, but said he doesn't support everything Bannon does. Mercer said he had been wrong to support activist provocateur Milo Yiannopoulos. He cited that error in his decision to pass his stock to his daughter, a conservative activist.

The elder Mercer will remain active at Long Island-based Renaissance, but no longer as co-CEO.

Mercer is also an investor in the data firm Cambridge Analytica, which worked for Trump's presidential campaign. According to Wikileaks founder Julian Assange, the firm offered to cooperate with his efforts to post documents embarrassing to Trump's Democratic opponent, Hillary Clinton. Special Counsel Robert Mueller has been investigating Russian ties to activists in the 2016 Presidential election.

Mercer's role in making Bannon a Trump adviser was criticized by David Magerman, a Rennaissance data scientist and  restaurateur based in Lower Merion. Magerman cited Bannon's popularity among white-nationalist groups.

In his letter Mercer said he supports racial equality, and didn't mention Magerman or Cambridge Analytica. Magerman's lawyer William Harvey had no comment.

Magerman left Mercer earlier this year after denouncing Mercer's political involvement in an article in the Wall Street Journal and a manifesto first posted in my column.

From Mercer's Nov. 2 letter:

"During the past year, I have been the object of a great deal of scrutiny from the press. … I have decided to correct some of the misinformation. …

"I believe that individuals are happiest and most fulfilled when they form their own opinions, assume responsibility for their own actions, and spend the fruits of their own labor as they see fit.

"I believe that a collection of individuals making their own decisions within the confines of a clear and concise set of laws that they have determined for themselves will advance society much more effectively than will a collection of experts who are confident in their knowledge of what is best for everyone else.

"This is why I support conservatives, who favor a smaller, less powerful government …

"Of the many mischaracterizations made of me by the press, the most repugnant to me have been the intimations that I am a white supremacist or a member of some other noxious group.

"Discrimination on the basis of race, ethnicity, gender, creed, or anything of that sort is abhorrent to me. But more than that, it is ignorant.

"The press has also intimated that my politics marches in lockstep with Steve Bannon's. I have great respect for Mr. Bannon, and from time to time I do discuss politics with him. However, I make my own decisions with respect to whom I support politically. Those decisions do not always align with Mr. Bannon's …

"I supported Milo Yiannopoulos in the hope and expectation that his expression of views contrary to the social mainstream and his spotlighting of the hypocrisy of those who would close down free speech in the name of political correctness would promote the type of open debate and freedom of thought that is being throttled on many American college campuses today.

"But in my opinion, actions of and statements by Mr. Yiannopoulos have caused pain and divisiveness undermining the open and productive discourse that I had hoped to facilitate. I was mistaken to have supported him …

"For personal reasons, I have also decided to sell my stake in Breitbart News to my daughters …

"I am 71 years old, the same age that [former Mercer chief] Jim Simons was when he retired. I do not plan to retire, but I do plan to relinquish my management responsibilities."