Facebook’s board backed Chief Operating Officer Sheryl Sandberg’s handling of research into investor George Soros, the Wall Street Journal reported on Wednesday, citing a letter from the board.

Sandberg was being truthful when she said she did not know that the social network hired a public relations firm to explore Soros’ criticisms of the company, the Journal reported.

Sandberg’s request to probe whether Soros shorted Facebook stock was “entirely appropriate,” the Journal reported, citing the letter.

Facebook was not immediately available for comment.