Facebook Inc. s FB Oversight Board said Thursday that the social-media company has not been fully forthcoming when it comes to providing the board with information about its cross-check system, through which the company is said to have held higher-profile users to different standards when it comes to enforcement of Facebook rules. Following a Wall Street Journal investigation into the cross-check system, Facebook's Oversight Board began looking into the program and found that Facebook sometimes failed to provide relevant information. In other cases the company provided incomplete information. The Oversight Board said in a Thursday blog post that it has accepted a request from Facebook to review the cross-check system and provide recommendations on potential changes. Specifically, Facebook requested guidance on, among other things: how to ensure fairness and objectivity in cross-check reviews, taking into account context; how to govern cross-check and promote transparency; and the criteria it uses to determine who is included in cross-check and how to ensure this is equitable, according to the blog post. Shares of Facebook have gained 25% so far this year as the S&P 500 SPX has risen 21%.