If you have any doubt just read this about Zurich Financial Services in the FT.
As the FT noted:
Many mutual funds prohibit rapid turnover trading as it can increase transaction costs and siphon profits from long-term investors. Zurich helped the hedge funds evade the mutual funds' "timing police" by setting up special-purpose vehicles that allowed the hedge funds to trade under disguised identities.
Zurich admitted no wrong doing. But as is commonplace when no wrong-doing has happened paid a fine of $4 million and repaid profits earned of $12.8 million.