Go-anywhere camera maker GoPro (NASDAQ:GPRO) went public last week and instantly became an investor’s darling. The shares have climbed every day since the IPO, at least until today. However, it appears GoPro shares are finally taking a breather on Wednesday, having doubled from the $24 IPO price just five trading days ago.

GoPro

GoPro shares are down $5.70 to $43.10 in active trading as of 2:12 PM ET Wednesday.

GoPro heavily shorted already

A number of analysts have noted that the short interest in GoPro is likely rising. Karl Loomes, a market analyst with SunGard’s Astec Analytics, says it looks like almost all of the available shares to short against GoPro have already been spoken for.

Loomis explains the significance below. “Although still early days, data from SunGard’s Astec Analytics shows the cost of borrowing GoPro shares — borrowing being the prerequisite of short selling them — has immediately become one of the highest on our system. Likewise the utilization level, i.e. the percentage of shares that are available on loan actually being borrowed, is near 100% — again one of the highest on our system. Together both these figures suggest borrowers are snapping up all the available GoPro shares they can, and are willing to pay a high price to do so.”

Essentially “normal” trading activity

“It wouldn’t surprise me if this is a bet against the immediate increase in share price and not necessarily a bet against the company,” Loomes said in a recent phone interview with Business Insider.

Investment pros also emphasize that volatility in both directions is to be expected, especially with an IPO that doubles in just a few trading days.

It’s fair to say that even in a very big year for IPOs, GoPro’s bolting out of the gate was clearly notable, and now after the big run up, it seems the other side of that trade is sensing it’s their turn to make a move.