Rumors swirling for the past couple weeks have turned out to be true. 3D printing titan Stratasys and the number one personal 3D printer company MakerBot have announced the signing of a definitive merger agreement. The privately held MakerBot will merge with a subsidiary of Stratasys in a stock-for-stock transaction.

MakerBot has sold more than 22,000 3D printers since 2009. In the last nine months, the MakerBot Replicator 2 Desktop 3D Printer accounted for 11,000 of those sales. Bre Pettis, CEO and co-founder of MakerBot, will continue to lead the company.

Stratasys is one of two public giants in additive manufacturing/3D printing. The other is 3D Systems, which has its own line of personal class offerings in the Cube and CubeX. With the acquisition of MakerBot, Stratasys can immediately assume a leading position in the personal 3D printing category, which has been the fastest growing segment of additive manufacturing for the past few years. Of course, Stratasys also gets Thingiverse.com as part of the deal, the popular 3D printing enthusiast community and file sharing site.

Upon completion of the transaction, MakerBot will operate as a separate subsidiary of Stratasys, maintaining its own identity, products and go-to-market strategy. The merger is expected to be completed during the third quarter of 2013 and it is subject to regulatory approvals and other conditions customary for such transactions.

"MakerBot's 3D printers are rapidly being adopted by CAD-trained designers and engineers," said David Reis, Stratasys CEO. "Bre Pettis and his team at MakerBot have built the strongest brand in the desktop 3D printer category by delivering an exceptional user experience. MakerBot has impressive products, and we believe that the company's strategy of making 3D printing accessible and affordable will continue to drive adoption.  I am looking forward to working with Bre," added Reis.

"The last couple of years have been incredibly inspiring and exciting for us," noted Pettis. "We have an aggressive model for growth and partnering with Stratasys will allow us to supercharge our mission to empower individuals to make things using a MakerBot, and allow us to bring 3D technology to more people. I am excited about the opportunities this combination will bring to our current and future customers."

Under the terms of the merger agreement, Stratasys will initially issue approximately 4.76 million shares in exchange for 100% of the outstanding capital stock of MakerBot. The proposed merger has an initial value of $403 million based on Stratasys' closing stock price of $84.60 as of June 19, 2013. MakerBot stakeholders also qualify for performance-based earn-outs that provide for the issue of up to an additional 2.38 million shares through the end of 2014. The proposed earn-out payments have an initial value of up to $201 million based on the Stratasys closing stock price as of June 19, 2013. Those payments, if earned, will be made in Stratasys shares or cash (in an amount reflecting the value of the Stratasys shares that would have otherwise been issued at the relevant earn out determination date), or a combination thereof, at Stratasys' discretion.

Stratasys intends for MakerBot to operate as a separate subsidiary, preserving its existing brand, management, as well as the spirit of collaboration it has built with its users and partners. Together with Stratasys, MakerBot will continue to innovate, expand its product offering, provide attentive service to its users and make more 3D printing content available through Thingiverse.com.

Upon completion of the merger, Stratasys and MakerBot will jointly develop and implement strategies for building on their complementary strengths, intellectual property and technical know-how, and other unique assets and capabilities.

Stratasys and MakerBot will host a News Conference at MakerBot's headquarters located at One MetroTech Center (Jay Street) 21st Floor, Brooklyn, New York on Thursday, June 20 at 10 am Eastern Time.

Trivia: MakerBot is now the first personal 3D printing manufacturer able to use the term FDM (Fused Deposition Modeling) without infringing a Stratasys trademark. The term FFF (Fused Filament Fabrication) is a widely adopted replacement in the personal class to avoid the infringement.