A record $77.4 billion flooded into stock mutual funds and exchange-traded funds in January, a worrisome indicator for the stock market, according to TrimTabs Investment Research.

“As we survey the liquidity landscape, we increasingly do not like what we see,” TrimTabs analysts write in a report obtained by Barron’s.

“Investors are piling into stocks at a record pace, while companies are no longer supporting share prices. In the past, a combination of massive investor buying and net corporate selling has often coincided with market tops.”

Editor's Note: Billionaires Dump Stocks. Prepare for the Unthinkable.

As for corporations, their buybacks dropped to an eight-month low of $17.9 billion in January. Buybacks during earnings season have averaged just $900 million a day, the lowest total since July-August 2009, according to TrimTabs.

“As investors stampede into equities, corporate America seems to be turning less upbeat,” the firm says.

At the same time, TrimTabs analysts think the Federal Reserve’s massive easing operation is brewing bubbles in everything from junk bonds to leveraged loans, to farmland.

Others too are worried about the retail dash into stocks, including Vanguard Group founder John Bogle.

Individual investors are often a contrarian signal for the market — they buy at highs and sell at lows, he tells CNBC. “When mutual fund investors pile into equities, it's usually a very negative sign for the market.”

As a result, Bogle isn’t too impressed with the Dow Jones Industrial Average’s recent rally to 14,000, calling it merely “noise.”

Editor's Note: Billionaires Dump Stocks. Prepare for the Unthinkable.