Sept 3 (Reuters) - The U.S. securities regulator has been asking money managers to explain the standards they use for classifying funds as environmental, social and governance (ESG)-focused for several months, according to two sources familiar with the queries. U.S. Securities and Exchange Commission staff have been pressing firms for details on how they determine these classifications, two sources with direct knowledge said. Earlier this year, the regulator said it had found "potentially misleading" claims and inadequate controls around investing in ESG issues in a review of investment advisors and funds. SEC examiners have been scrutinizing investment advisers in recent months, including seeking information about how they are dealing with other jurisdictions, one of the sources said of the inquiries, which were reported earlier by Bloomberg News. The agency did not respond to a request for comment. Separately, the SEC has deployed a specialized team to examine misconduct related to climate change and other ESG issues. With a record $51 billion flooding into sustainable U.S. funds in 2020 alone, according to Morningstar, investors need to be better informed, the SEC says. read more The regulator is probing Deutsche Bank"s asset manager over how it used sustainable investing criteria to manage its assets, sources familiar with the investigation said last week. read more