The Securities and Exchange Commission this month issued guidance concerning Regulation M, which governs prohibited conduct by underwriters in connection with initial public offering allocations. Some experts say the move will chill the ability of underwriters to say anything to customers about the aftermarket in connection with hot IPOs.

Paul Uhlenhop, a securities lawyer at Chicago’s Lawrence Kamin Saunders & Uhlenhop, told Compliance Week that much of the SEC’s guidance constitutes little more than a “clarification of a longstanding policy,” but said that the tone of the release could make life difficult for some, and would “leave customers confused, frustrated and hurt in some monetary aspect.”