It was the latest blow for the storied investment bank, which has long supplied senators and cabinet secretaries to Washington but now draws comparisons to a "great vampire squid wrapped around the face of humanity."
In an opinion column in Wednesday's Times, Greg Smith, who worked in equity derivatives, said Goldman had become "as toxic and destructive as I have ever seen it.
"It makes me ill how callously people talk about ripping their clients off. Over the last 12 months I have seen five different managing directors refer to their own clients as 'muppets,'" Smith said.
In the United States "muppet" brings to mind lovable puppets like Kermit the Frog, but in Britain, "muppet" is slang for a stupid person.
Goldman Sachs issued a short statement in response:
"We disagree with the views expressed, which we don't think reflect the way we run our business. In our view, we will only be successful if our clients are successful. This fundamental truth lies at the heart of how we conduct ourselves."