The latest data from the Commodities Futures Trading Commission show "managed money"—hedge funds and the like—are net short 401 contracts of copper, worth roughly $31.6 million. This is the first time shorts outweighed long positions by managed money accounts since April.
Copper is down 7.4 percent this year, while gold, silver, aluminum and platinum are all positive.
Some of the increased copper shorting can likely be pegged on investigations by the Chinese government into loans that use copper as collateral. However, Gina Sanchez, founder of Chantico Global, thinks there are other macro reasons for the increase in bets that copper will fall.
"This short move in terms of hedge funds is consistent with recent downward revision of expected growth," said Sanchez, a CNBC contributor. "The World Bank has recently downgraded their expectations for 2014 growth, and that was primarily centered in the emerging markets; the BRICs were at the top of those downgrades."
While Sanchez believes copper hasn't been the best economic indicator in recent years, she sees the divergence in performance between copper and precious metals signaling a problem in the economy. "If you look where that money is flowing into, it's been flowing into silver and gold," she said. "What traders are saying is, 'Maybe the growth story isn't as strong as we thought, and this copper move could actually be the beginning of something bigger.'"
In terms of the charts, Auerbach Grayson global technical strategist Richard Ross sees stormy weather ahead.
Currently at $3.14 per pound, Ross notes that copper is trading below its technically significant 200-day moving average, which is now at $3.20.
"We really struggle here with that 200-day moving average," Ross said. "So [that's] a real problem here in the short-term."
Copper's long-term chart is even more worrisome for Ross. That's because he sees a bearish descending triangle that has formed since the start of 2011, with $3 as a support level. "This should be a continuation pattern to the downside," Ross said. "Any break below [$3], just as the charts suggest, would really set the stage for a bigger, more dramatic move down in copper, and perhaps finally give us a signal that that global growth story and the demand from emerging markets and China is really on its way out."
To see the full discussion on copper, with Ross on the technicals and Sanchez on the fundamentals, watch the above video.