Soros Philanthropy President Calls for U.S. Lawmakers to Review Facebook

Mr. Schrage also said Facebook asked Definers to look into Mr. Soros after the liberal philanthropist called internet “monopolies” a “menace” in a January speech at the World Economic Forum. “We had not heard such criticism from him before and wanted to determine if he had any financial motivation,” Mr. Schrage wrote. “Definers researched this using public information.”

The Facebook memo was reported by The Wall Street Journal and other media outlets Tuesday. Facebook posted it in on its site on Wednesday evening.

In response to Facebook’s memo, Patrick Gaspard, president of Mr. Soros’s Open Society Foundations, said in a tweet on Wednesday: “So @facebook decides to drop a turkey on Thanksgiving eve, with admission that Definers was tasked by company leadership to target and smear George Soros because he publicly criticized their out of control business model. Sorry, but this needs independent, congressional oversight.”

In the Facebook memo, Mr. Schrage said the company asked Definers to explore the link between an anti-Facebook group called Freedom from Facebook and Mr. Soros. Definers “prepared documents and distributed these to the press to show that this was not simply a spontaneous grass roots movement,” the memo said.

Mr. Schrage added: “Some of this work is being characterized as opposition research, but I believe it would be irresponsible and unprofessional for us not to understand the backgrounds and potential conflicts of interest of our critics.”

Freedom from Facebook has said it gets no funding or support from Mr. Soros, who in a statement last week called Facebook’s tactics “unsavory.”

Mr. Gaspard in a statement to the Journal on Thursday said Open Society Foundations “proudly funds a range of organizations that are concerned about the power of platforms, disinformation, and the spread of fake news. Some of those organizations have joined the Freedom from Facebook campaign though OSF did not fund them to do so.”

Mr. Schrage’s admission of his role in hiring Definers could deflect some of the blame from Facebook Chief Executive Mark Zuckerberg and operating chief Sheryl Sandberg, who had said they found out about Definers through the Times article.

In a response to Mr. Schrage’s internal post Tuesday, Ms. Sandberg said Definers’s work was incorporated into materials presented to her and she received a “small number of emails where Definers was referenced.”

Definers on its website Wednesday said “we are proud of our work with Facebook.” It said the characterization of its work as a smear campaign against Mr. Soros and anti-Facebook groups is “completely false.”

Mr. Zuckerberg and Ms. Sandberg have come under fire by investors, lawmakers and employees for a series of management missteps, including Facebook’s response to uncovering evidence of Russian manipulation during the U.S. presidential race in 2016 and efforts to stem the spread of misinformation on the platform.

Mr. Schrage said in the memo that over time more people at Facebook worked with Definers on more projects, making the relationship less centrally managed. “I should have known of the decision to expand their mandate,” he wrote. He didn’t address who made the decision to expand the mandate.

“Responsibility for these decisions rests with leadership of the communications team. That’s me,” Mr. Schrage wrote in the memo. “Mark and Sheryl relied on me to manage this without controversy,” he said, referring to Mr. Zuckerberg and Ms. Sandberg.

In a TV interview with CNN on Tuesday, Mr. Zuckerberg said he was reviewing Definers’s work with Facebook after breaking ties with the firm. “So far, it doesn’t appear that anything that the group said was untrue,” Mr. Zuckerberg said in the interview.

Write to Deepa Seetharaman at Deepa.Seetharaman@wsj.com