Complex sentence: In late 2011, a major scandal arose involved allegations that Bell Pottinger, one of the largest UK-based lobbying and public relations companies, had manipulated articles on behalf of its clients.
Split into simpler sentences: In late 2011, a major scandal arose involving Bell Pottinger, one of the largest lobbying and public relations companies in Britain. The incident involved allegations that Bell Pottinger had manipulated articles on behalf of its clients.