If George Muzea is right, Monday's decline is just the start.

Muzea, who runs Reno-based Muzea Insider Consulting Services, has been negative on the market for just two weeks — the first time he has been bearish since July 24, when he turned positive.

Muzea makes market calls based on the activity of corporate insiders. He's considered the grandfather of the insider-tracking industry, generally keeping a low profile to all but his high-paying hedge fund clients.

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We speak every now and then. When we spoke last week he gave me an earful that I only wish now I had published then. (Such is life! The Thanksgiving break was calling.) But, according to Muzea, this is likely the beginning of a sharp and steep decline not unlike the one that hit the market last spring — and maybe worse.

The only thing he doesn't know is whether, as is often the case, he is a month or two early. The wild card on timing, he says, is the impact 401k money will have inflows in January, which could give the market one last gasp into early spring. He'll know, he says, if insiders stop selling early in the year.

Muzea notes, however, that insiders have been finding less value in the market over the past eight years. "Every time you have a low," he says, "you have fewer and fewer stocks with positive patterns."

Before you go calling this a scare tactic on a down day, keep that Muzea has a record, and he is basing his forecast on a history of following the market as it relates to the actions of insiders. "If you want to lose money over a long period of time," he says, "buy when insiders are selling and the public is bullish." (Regular readers will remember his name from a few very good calls in the past.)

Adding to the intrigue this time, he says, is the increasingly powerful role of electronically traded funds. "The players and numbers of ETFs are expanding exponentially, and they're putting that money into EFTs" that track indices like the Nasdaq 100 or the S&P 500. The most disconcerting part of the story, he says, is that these investors what have flocked into the ETFs don't need an uptick — or a rise in prices — to sell them short. "If the market is vulnerable right now," he asks, "what would happen if a geopolitical event or something else happens? How fast would it take for the Dow to go down 500 or 700 points, with everybody going short to protect themselves? When they start selling these, who is going to buy them?"

The concern, of course, is that the answer will be: Nobody.

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