If you're waiting for desktop additive-manufacturing technology to move closer to professional-level results, be prepared to wait for a very long time. The past year was a breakout for desktop 3-D printing. MakerBot released two new models, Formlabs debuted the first prosumer 3-D printer to use high-accuracy stereolithography, and a slew of innovative, printed projects lifted awareness and desirability of additive manufacturing for the general public. But the year ended with a legal hiccup. Formlabs will be dealing with a patent infringement lawsuit brought against them by 3D Systems, one of the biggest players in the industry. The hobbyist segment of the industry has been built on the back of expired patents, but as the Electronic Frontier Foundation has pointed out, many patents that will be required to advance the state of the art will not expire for years or even a decade. We've uncovered 10 patents that could severely stifle innovation in the low-cost segment of the 3-D printing market and keep you from making colorful, smooth-finished figures and precise, articulating parts. These patents cover core technologies and ease-of-use features, and could take momentum from the upstarts and return it to the entrenched companies. Above: High temperature modeling apparatus Patent Number: 6,722,872 Date Issued: April 20, 2004 Assignee: Stratasys Who Should Be Worried: Anyone who makes a "Fused Filament"-style 3-D printer (e.g., MakerBot, RepRap projects, UP!, Cubify) Manufacturing with plastics, whether injection molding or 3-D printing, is a tricky business. As plastic cools, it shrinks, and that shrinkage can cause deformation. High-end printers combat this by keeping the build chamber at a high temperature throughout the build process to mitigate warping. Stratasys received the patent for this feature in 2004. Popular home-based 3-D printers have open build chambers, meaning an errant breeze can chill plastic and destroy hours of print work. The photograph above shows several experiments a maker had to run in order to deal with the effects of temperature variability on his parts. This patent means RepRap derivatives won’t be able to incorporate a warming chamber and reduce this kind of experimentation until 2021. While not a deal breaker now, as we move beyond the "gee whiz!" phase of 3-D printing in the home, it will become increasingly important. Photo: Zheng3

Photo: Thingiverse Smoothing method for layered deposition modeling Patent Application Number: 8,123,999 Date Published: Feb. 28, 2012 Assignee: Stratasys Who Should Be Worried: Any company that makes a printer that produces plastic parts with a rough texture. One of the drawbacks of fused filament fabrication, the process used by RepRaps, MakerBots, and most hobby-grade machines, is a rough, ridged surface that looks more like a kindergartener's clay pot than the future of manufacturing. This substandard surface can be removed by hand with sandpaper and hours of effort. Or parts can be smoothed out effortlessly with a chemical processes that reduces the ridges uniformly, leading to higher-quality parts. Stratasys has patented a method to achieve this slick surface finish by submerging parts in a liquid bath that melts the plastic — basically, anti-wrinkle cream for 3-D printers.

Photo: Stratasys Soluble material and process for three-dimensional modeling Patent Number: 6,790,403 Date Granted: Sept. 14, 2004 Assignee: Stratasys Who Should Be Worried: Four words. Anyone. Who. Makes. Plastics. This particular patent covers soluble print materials that can be used to support a plastic part during the printing process and removed chemically after the fact, revealing a product that would be unprintable otherwise. Stratasys takes materials seriously and has many other patents that protect their plastics, including on the optimal design of filament.

Photo: Sandboxr Three-dimensional printing techniques Patent Number: 5,387,380 Date Granted: Feb. 7, 1995 Assignee: Massachusetts Institute of Technology Who Should Be Worried: Anyone who wants to print full-color models. MakerBot and the RepRap project have utilized expired patents on fused filament fabrication techniques to launch the consumer 3-D printing revolution. Formlabs believes they are working within the scope of expired core stereolithography patents to continue the trend. ZCorp’s full-color printing patents (which were licensed from MIT), filed in the early 1990s and on the brink of expiration, would seem like the next logical target. Entrepreneurs in this space will have to tread lightly. Not only has ZCorp continued to file patents on their full-color powder/binder technology, many of their printers utilize HP printheads. This means hackers will have to contend with the giant 2-D printer maker's broad swath of patents as well as its 3-D printer counterpart. Since this is the only technology that enables full-color 3-D printing, it will create limitations for anyone who wants to make their Minecraft realms, or any videogame characters, real.

Photo: Objet Preparation of building material for solid freeform fabrication Patent Application Number: 12/327,857 Date Published: Nov. 1, 2012 Assignee: Objet Geometries Who Should Be Worried: No one. Yet. Objet has a patent that covers the dynamic production of plastics for 3-D printers. Their “Digital Materials” allow designers to create new composite materials with varied structural and aesthetic properties. These machines can produce parts that feature hard plastic, rubbery elastomers, and transparent forms, all in the same piece, produced at the same time. No low-cost 3-D printer manufacturers are trying anything so ambitious, but this patent could serve to keep upstarts from trying. On the other hand, this patent has yet to be granted, and the 32 claims enumerated in the application describe a very specific embodiment that leaves plenty of room for alternate approaches to the problem.

Image: Shapeways Distributed rapid prototyping Patent Application Number: 11/818,521 Date Published: Dec. 18, 2008 Assignee: 3D Systems Who Should Be Worried: Shapeways, Ponoko, FigurePrints, etc. Patents don’t just cover hardware — business methods are fair game as well. In that regard, 3D Systems filed a broad patent that attempts to cover a system that accepts 3-D CAD files, queues them up for production, load-balances the machines, and reports analytics on the entire setup. The patent describes the invention that follows: The three-dimensional modeler receives, via a network interface, a build including information for use in generating a physical representation of a three-dimensional model. A queuing mechanism is used to determine the order in which builds are processed by a three-dimensional modeler. Processing of the build includes instructing hardware of the three-dimensional modeler to create the physical representation of the three-dimensional model. The network interface of the three-dimensional modeler may include a web server. The network interface may also be used to send diagnostics and receive feedback such as calibration data based on the diagnostics. The network interface may also be used to receive software code or data upgrades. The network interface may also be used to order supplies for the three-dimensional modeler." Essentially, a system that works just like every 3-D printing service that has launched in the past few years. If granted, this patent could crush the hopes of companies looking to turn 3-D printing into a service business.

Photo: Stratasys Filament container and methods of use thereof Patent Number: 8,157,202 Date Granted: April 17, 2012 Assignee: Stratasys Who Should Be Worried: Any maker of printers that extrude plastic from a coil. Stratasys has developed filament spools that keep plastic protected and prepared for the 3-D printer, a very helpful feature from a technical and sales perspective. Not only that, but they've also created systems that automatically switch spools of filament when one is empty or when a different color is required. One of the major strengths that the large 3-D printer manufacturers possess are decades of understanding and responding to user needs. They've seen what power users need from these machines, they have the engineering resources to pursue multiple solutions (from the printer itself to the humble spool that holds the filament) and the capital to file applications to protect as many embodiments of the invention as possible. For instance, in addition to their liquid smoothing process from the last example, they've also patented a similar process that replaces the liquid bath with a vapor chamber that achieves the same effect. They've found multiple ways to reduce print time, fixed small problems like hiding the seams that form in filament based 3-D printing, and and of course, filed patents to safeguard these inventions. These companies that have built the market for 3-D printing over the last decades have also built fortresses of patents that will be challenging for startups to surmount.

Photo: 3D Systems Support volume calculation for a CAD model Patent Number: 6,907,307 Date Granted: June 14, 2005 Assignee: 3D Systems Who Should Be Worried: Customers who value usable software. While it may be horrifying to some in the tech world, 3-D printer companies have filed and received patents on many software features. One example is the ability to see how much support material a model will require — a feature patented by 3D Systems, unavailable to others until after 2018. Another example is a software feature that automatically places multiple models on the same build platform, maximizing the space, patented by Stratasys and locked up until the roaring 2020s.

Photo: 3D Systems Apparatus and method for aligning a removable build chamber within a process chamber Patent Number: 7,357,629 Date Granted: April 15, 2008 Assignee: 3D Systems Who Should Be Worried: 3-D printer manufacturers who care about user experience. As 3-D printers become more popular, the raw speeds and feeds will start to take a back seat to creature comforts. For instance, the new Cubify 3-D printer from 3D Systems touts a Wi-Fi connection and plug and play cartridge system as key selling features. The system described in this patent is made up of an external support frame, a variety of alignment features and connections, and a build chamber that can be easily taken out and relocated to a workshop where the 3-D printed part can be removed, cleaned, and finished. Like rubber grips on a toothbrush the goal isn't to do the job better, just more comfortably