The cancellation may be stoking takeover speculation, said Angelo Zino, an equity analyst from S&P Capital IQ in New York.

“We’re definitely viewing them as more of a potential takeover than we have in a long time,” Zino said in a phone interview.

Makers of 3-D printers, which layer materials to create objects, have been frequently speculated as takeover targets since Stratasys Ltd. bought startup MakerBot Industries LLC for about $400 million last year. The printers are gaining in popularity as they become more affordable, and the market is expanding after generating as much as $2.9 billion in revenue worldwide last year.

And 

Wamsi Mohan, an analyst with Bank of America Corp., said 3D System’s rally over the last two weeks has been driven by high short interest “compounded by extremely limited borrow resulting in very high borrowing costs driving a de-risking rally.” Mohan still recommends selling the shares.

The stock has risen 30 percent since June 12. Almost 19 percent of 3D Systems’ shares outstanding were sold short as of June 30, according to data compiled by Markit Securities Ltd.

?3D Systems is still likely to pursue more takeovers this year, Mohan wrote in a research note today.

Eoin Treacy's view

The 3-D printing sector has experienced a great deal of consolidation in the last few years as the major participants embarked on an aggressive acquisition campaign. Following powerful accelerations the respective shares pulled back sharply as the challenge of absorbing technologies and alien company structures took its toll on productivity. Despite the fact that they have lost consistency, the fact remains that additive manufacturing and rapid prototyping represent a growth industry which is likely to play an increasingly important role in the industrial sector. 

Stratasys’ three week rally has pressured shorts and suggests the $85 area represents a medium-term area of support. The short covering rally may have run its course and the loss of consistency following its two-year uptrend, the most likely scenario remains for ranging. 

3-D Systems fell more from the January peak and subsequently rallied less. It will need to hold the $45 area on the next pullback to confirm an area of medium-term support has been reached. 

The Exone has also rallied to break this year’s progression of lower rally highs. It will need to hold above or in the region of $35 on the next pullback in order to demonstrate medium-term support has been found.