Morgan Stanley jolted the legal industry last week with a letter urging its outside law firms to return their attorneys to the office. Now some law firms—including those that have built their business models around remote work—are pushing back.

Some “virtual” or “distributed” firms have even done work for Morgan Stanley, whether now or in the past, according to lawyers at such firms. For instance, one attorney who previously worked at a large virtual firm expressed surprise at the letter written by chief legal officer Eric Grossman, saying he had never heard of the bank’s office preferences while working with the client.