Short interest levels varied from flat (Exone) to surging in the case of Stratasys, which now lies above 13%, up 11.14% so far this year. Short interest in 3D Systems is also up by a third to 19.4% in the last seven months, making it the most shorted company in the business.

“A range of competitors have flooded into the 3D printing market,” said Simon Colvin, analyst at Markit.

“Tech giants don’t want to miss out on this growth opportunity. IBM, HP and even Amazon have entered the 3D printing market in one form or another. Although the complexity of printing should not be underestimated, these firms have far more resources and may eventually drive margins down.”

The average return of the five firms is -29% year to date, suggesting that the success they saw at the end of 2013 was unsustainable.

In 2013 3D printing stocks were characterised by strong revenue growth, rising stock prices, and shorts running for the exit after experiencing agonising losses after the likes of 3D Systems and Stratasys returning 860% and 340% respectively, catching short sellers out.

Voxeljet proved to be the worst performing of the lot, after an extremely volatile US IPO last October. Listed at $15, stocks soared to $70, and have since crumbled to $19.