FRANKFURT (Reuters) -The U.S. Securities and Exchange Commission is investigating Deutsche Bank’s asset manager DWS over how it used sustainable investing criteria to manage its assets, two people with knowledge of the matter said on Thursday. The news, first reported by The Wall Street Journal, sent DWS shares down almost 13% in morning trade. The two people spoke to Reuters on condition of anonymity because they were not authorized to discuss ongoing investigations. DWS and Deutsche Bank declined to comment. If it progresses, the case will be watched closely by the asset management industry….