Here we go again.

Yesterday afternoon, I received a press release from the National Association of Securities Dealers (NASD) announcing that the organization, which is best known as the governing body for the NASDAQ National Market, has censured and fined American Express Financial Advisors, Chase Investment Services, and Citigroup Global Markets for improperly pushing mutual funds.

At issue is how the brokerages, which, respectively, are units of American Express (NYSE:AXP), JPMorganChase (NYSE:JPM), and Citigroup (NYSE:C), recommended and sold Class B and C shares of mutual funds without disclosing that Class A shares might have been more economically advantageous. Indeed, Class B or lower shares are typically an awful deal for investors. Class B shares, in particular, usually carry contingent deferred sales charges for up to six years. Can you imagine wanting to exit a fund after a five-year losing streak only to be told that you'll have to pay a hefty sum for the privilege of doing so? Yeah, me either.

But think about how your broker makes out on a deal like that. They'll earn a portion of the proceeds from your expense ratio annually, and then rake in a tidy sum when you've finally had enough. No wonder Motley Fool Champion Funds chief analyst Shannon Zimmerman suggested the title for this story when I forwarded the press release to him. Pushing Class B and C shares is nothing less than a money grab by greedy brokers.

Fortunately, the NASD knows this. In the statement, Vice Chairman Mary Schapiro said that brokers must consider the cost to the client when recommending funds that offer different share classes. American Express, Chase, and Citi apparently didn't do that, and they've been fined more than $21 million for their misbehavior.

Yet that's peanuts to these guys, so you can expect the practice to continue. And that means you, dear Fool, must remain on the front lines when it comes to defending your mutual fund portfolio. Don't get suckered. Stick with Class A shares or, even better, funds that offer only one class of shares in a low-cost, high-performance package. Those are the champion funds.

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You can beat the market with funds, and it won't cost you a fortune to do so. Let us help. Take a risk-free, 30-day trial to Motley Fool Champion Funds today.

Fool contributor Tim Beyers prefers stocks but he's also an awfully happy owner of the Julius Baer International Equity Fund and has been for two years now. What funds are you investing in? Share your thoughts with other Fools at the Mutual Funds discussion board. Tim didn't own shares in any of the companies mentioned in this story at the time of publication. You can find out what's in his portfolio by checking Tim's Fool profile, which is here. The Motley Fool has a disclosure policy.