Following Greg Smith’s highly publicized resignation and assail of its culture, Goldman Sachs Group Inc. has been searching emails and internal communication for evidence of derogatory comments about clients. “Muppet” is the center of the search, which Smith claims five managing directors used to refer to clients in the last 12 monts. In the United Kingdom, where Smith worked, the word generally means idiot. “We take the concerns of our employees seriously and that is why we have looked into the allegations Mr. Smith made,” says a spokesman for the company confirming the email searches. Smith’s resignation and concerns about the “toxic” environment at Goldman Sachs were published in a New York Times op-ed piece March 14.