Firms should have specific policies and procedures that adequately prevent “front running” of investing client trades. These procedures should include restricted periods before and after issuing a research report. Restricted periods of at least 30 calendar days before and five calendar days after report issuance are recommended, with exceptions permitted on the announcement of significant news or events by the subject company if investing clients are given adequate notice and the ability to trade. _ However, restrictions on purchases or sales of securities need not apply to the securities of a diversified investment company or other investment fund over which the covered employees or members of their immediate families have no investment discretion or control _
Can someone explain that last sentence in more detail?
many thanks