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These days, 3-D printing is big news.1 The use of 3-D printing and other related technologies is seen as having potentially transformative implications. “Just as the Web democratized innovation in bits, a new class of ‘rapid prototyping’ technologies, from 3-D printers to laser cutters, is democratizing innovation in atoms,” Wired magazine’s longtime editor-in-chief, Chris Anderson, stated in his new book Makers: The New Industrial Revolution.2 “A new digital revolution is coming, this time in fabrication,” MIT professor Neil Gershenfeld wrote in a recent issue of Foreign Affairs.3
But in addition to 3-D printing’s technological implications, recent evolutions in 3-D printing offer important management lessons for executives about the changing face of technological innovation — and what that means for businesses. In this article, we examine the rapid emergence of a movement called open-source 3-D printing and how it fits into a general trend toward open-source innovation by collaborative online communities. We then discuss how existing companies can respond to open-source innovation if it occurs in their industry — and whether such collaborative innovation projects represent a threat or an opportunity for existing businesses.
Trends in 3-D Printing
Also known as “additive manufacturing” or “rapid prototyping,” 3-D printing is the printing of solid, physical 3-D objects. Unlike machining processes, which are subtractive in nature, 3-D printing systems join together raw materials to form an object. Drawing on a computer-aided design (CAD) file, the design for an object is first divided into paper-thin, cross-sectional slices, which are then each ‘printed’ out of liquid, powder, plastic or metal materials in sequence until the entire object is created. The use of 3-D printing makes it possible to build physical models, prototypes, patterns, tooling components or production parts. Design and manufacturing organizations use it for product parts in the consumer, industrial, medical and military markets.
The longer-term implications of 3-D printing technologies are believed to be large.4 Direct advantages include enabling designers to operate more efficiently and conveniently. They can quickly prototype their designs in order to test their viability or demonstrate them. In addition, 3-D printing is increasingly used to manufacture products or parts in small batches that would be too costly for a traditional production line. Moreover, 3-D printing enables entirely new products to be developed. With layer-wise 3-D printing processes, many limitations of existing production processes are removed, allowing a wider range of design options. Widespread use of 3-D printing will also likely have implications for production, logistics and retail, since there will be less need to centrally fabricate products and distribute them if individuals can download and locally print a product’s design.
However, 3-D printing is not new. Industrial 3-D printing manufacturers have been offering their products for more than 20 years now. Their machines were initially sold to larger R&D-based organizations that require high-quality objects and are able to afford a premium price. Currently, more than thirty 3-D printing companies around the globe offer a range of industrial 3-D printing systems drawing on various technologies. More expensive systems produce fine-grained metal and polymer parts, while simpler systems use plastics to create 3-D objects. In 2011, total industry revenues for industrial and professional purposes had grown to more than $1.7 billion, including both products and services. The industry’s compound annual growth rate has been 26.4% over its 24-year history, and double-digit growth rates are expected to continue until at least 2019.5
In terms of unit sales, Stratasys Ltd., which now has headquarters in both Eden Prairie, Minnesota and Rehovat, Israel, is the world market leader in 3-D printing; Stratasys recently finalized a merger with Objet Ltd., an important producer at the higher end of the 3-D printing market. Another significant 3-D printing supplier is 3D Systems Corp., based in Rock Hill, South Carolina, which recently acquired a company known as Z Corp.6 Another major supplier is also EOS, based in Munich, Germany, a producer of higher-end 3-D printing systems.
While early systems were mainly sold to large, multinational customers, 3-D printing manufacturers more recently started to focus on the lower end of the market, offering increasingly cheaper machines to make 3-D printing a viable option for small businesses, self-employed engineers and designers, schools and individual consumers. Indeed, 3-D printing is expected to eventually become a mass market.7
In the past two years, 3-D printers for home use have emerged on the scene. Not very long ago, no such product existed, but thousands of 3-D printers for home use are now being made annually by new startup companies. Five years ago, users started to collaboratively develop home printer designs and to share their open-source designs on the Web. This attracted new users, some of whom also made innovative contributions, and an open-source 3-D printing community soon developed. More recently, users started to found their own businesses, which are now commercializing open-source-based 3-D printers.
How the 3-D Printing Market is Changing
Early 3-D printing systems were expensive — typically priced at $250,000 and more — and were designed for a limited market. Stratasys, for example, initially sold its products to major corporate customers such as General Motors and Pratt & Whitney for use in those companies’ internal R&D processes. As their technologies evolved, 3-D printing companies started to focus on the lower end of the market, and applications of 3-D printing for medical uses such as hearing aids and dental implants became more common. More recently, 3-D printing companies started to have success with systems priced at $10,000 to $30,000, making 3-D printing viable for schools and medium-sized enterprises. Stratasys also collaborates with traditional printing giant Hewlett-Packard Co., which is now selling Stratasys’s lower-end products as HP-branded machines. New companies are also forming to offer 3-D printing as a service. Shapeways Inc., for example, a spinoff of Dutch multinational Royal Philips Electronics, prints consumer designs using excess industrial 3-D printing capacity. Meanwhile, 3D Systems recently introduced its Cube, advertised as a home-use 3D printer, starting at $1,299.
The RepRap (replicating rapid prototyper) is an open-source home-use 3D printer whose popularity has grown quickly in the past three years. Like Stratasys’s machines, the RepRap’s design revolves around a heated nozzle from which a fine filament of molten plastic is extruded. The nozzle is then moved in X,Y and Z dimensions by computer-driven motors to successively create each layer of the object to be made. Since many of the RepRap’s parts are made from plastic, the machine can largely replicate itself, with a kit that anyone can assemble given time, materials and a minor investment, typically of about $400.
The RepRap was created in 2005 by Adrian Bowyer, a lecturer in mechanical engineering at University of Bath in the United Kingdom. Bowyer envisioned a machine that would be owned and used by people to make things at home. Bowyer shared his design for free under the GNU general public license. In its first two years, the project did not receive much attention, but after early members of the RepRap community managed to self-replicate the machine, adoption began to take off in the summer of 2007. By mid-2010, the size of the RepRap community was estimated to be more than 3,800 individuals and was estimated to be doubling every six months.8 More recently, in early 2012, an estimate of the total number of RepRap machines, including derivative commercial kits, was 29,745.9
Image courtesy of Makerbot Industries.
Thousands of enthusiasts built copies of the RepRap for themselves and collaboratively improved Bowyer’s original designs. It did not take long for some members of the RepRap community to start selling commercial versions of the RepRap. By 2012, user-founded companies were shipping thousands of machines annually, at prices of $2,500 or less. These are mostly offered as kits that buyers need to put together themselves. Such printers are more standardized, thus offering more reliability but at the expense of some flexibility, and it still takes an effort to get a RepRap operational. In the past year, however, user-founded companies started to offer fully assembled home-use 3-D printing systems. Examples of user-founded companies include Bits From Bytes, based in Clevedon, United Kingdom; Makerbot Industries, based in Brooklyn, New York; and Ultimaking Ltd., based in Geldermalsen, the Netherlands. (Ultimaking plans to change its name to Ultimaker soon.)
All three companies were founded by active RepRap community members who stepped into the lower-end market segment of 3-D printing, serving individual designers, artists, inventors and students. These open-source printers represent an incipient challenge to existing 3-D printer companies at the low end of the market. In response, 3D Systems, for example, acquired Bits From Bytes and Botmill, another user-founded business. 3D Systems also recently introducing a fully assembled Cube 3-D printer to serve individual end users.
Innovation by User Communities
The rapid growth of open-source 3-D printing is a typical example of the broader and emerging phenomenon of open collaborative innovation. An open collaborative innovation project involves contributors who share the work of generating a design and also reveal the outputs from their individual and collective design efforts openly for anyone to use. Contributors to such open-source projects typically contribute for personal need, enjoyment and/or reputational gains, to help others or to develop their skills.
While open-source communities are probably best known for software development, they are by no means restricted to software or even information products; as the RepRap community demonstrates, such communities are also viable for developing physical products. Moreover, innovation by user communities may be expected to increasingly compete with and, in some cases, displace corporate innovation in many parts of the economy. This shift is driven by new technologies — the transition to increasingly digitized and modularized design and production practices, coupled with the availability of very-low-cost, Internet-based communication — and a general trend toward better-educated citizens capable of engaging in innovation activities.10
Key questions for innovation-oriented companies then become:
1. Under what circumstances are companies most likely to see innovation by user communities?
2. Does user innovation pose a threat or opportunity for our company?
3. How can we respond — and how can generally useful innovations be identified from user communities?
Anything that can be cost-justified for development by a user collaborative and that does not involve significant economies of scale in replication and diffusion is theoretically a candidate for open collaborative innovation and diffusion. Such collaborative innovation is more likely to happen in three types of environments: nascent industries, industries where some potential users are not yet served and industries where some users are not served adequately.
Type 1: Nascent Industries A lot of innovation activity by users takes place in emerging new industries, when commercial markets do not yet exist or are still too small and uncertain to attract established companies. User communities may innovate and use new products prior to commercial production. The Wright brothers, for example, developed aircraft for personal need rather than anticipated commercial benefits. They were representatives of a worldwide community of aviation pioneers seeking after the “holy grail” of controlled flight, while commercial aviation companies emerged only later.11 Similar patterns have been witnessed in new sports such as kitesurfing, snowboarding and whitewater kayaking. Initially, users may justify their investments based on expected personal benefits, while commercial manufacturers must be concerned about a larger market potential upon which their profits depend. This uncertainty is reduced after a period of use and experimentation by early users. Accordingly, a common pattern of industry emergence is that users first innovate on their own, somewhat later in communities, while commercial production is seen only later, when demand is more certain.12
In the earliest days of 3-D printing, users were influential sources of innovation, too. While some incumbent 3-D manufacturers are academic spinoffs, Stratasys was founded by Scott Crump after he tried to make a toy frog for his young daughter using a glue gun loaded with a mixture of polyethylene and candle wax. His idea was to create the shape layer by layer. This triggered him to automate the process and invent the technology that became the heart of Stratasys’s products.13
Type 2: Existing Industries, Where Some Potential Users Are Not Yet Served After a new industry emerges, user communities can still be influential. The second type of industry in which this is the case is those in which some potential users are not yet served. This situation applies to products that are targeted initially toward high-end users able to afford the high prices necessary to overcome initial investment costs. For example, early cell phones were too expensive for a mass market and were mainly used by mobile professionals such as doctors; mass-market products were introduced and sold only later. Many high-technology industries, after their inception, can be characterized by a sequence in which only big customers are initially served — think of governments and multinational corporations. Medium-sized and small organizations follow later, and individual end consumers are served last, after the technology has sufficiently matured.14
Image courtesy of Makerbot Industries.
In such instances, user communities may emerge building their own versions of high-end products before a consumer version of the technology is widely available commercially. In particular, individual end users may collaborate to develop do-it-yourself personal products that are still insufficiently affordable for an individual. Such communities are most likely to form in the case of hobbyist products — when use provides enjoyment as opposed to providing pure economic benefit, and with significant lifestyle benefits. Beyond engaging in communities, hobbyist users are also more likely to found businesses to commercialize their inventions. Typically, they launch undertakings that might be viewed as costs, but which they consider fun and in line with their personal needs.15
The case of 3-D printing is an example of this type of industry. Commercial 3-D printers have been available for commercial purposes for 20 years, but the systems available for many years were expensive and mainly focused on high-end corporate customers. More recently, cheaper systems have made 3-D printing viable for basically all industrial users, but individual consumers had to create their own machines because low-end machines were still comparatively unaffordable. In effect, the RepRap community and its commercial spinoffs have jumped into the gap at the bottom of the market.
Type 3: Existing Industries, Where Some Users Are Not Adequately Served Another environment in which open-source innovation is likely is when commercial products have limited variety and are, in effect, one-size-fits-all. Manufacturers tend to follow product development strategies to meet the needs of homogenous market segments. They are motivated by perceived opportunities to serve sufficiently large numbers of users to justify their innovation investments, but this potentially leaves some users dissatisfied with the commercial products on the market. Especially when demand is heterogeneous, many users may not get precisely what they want, and some of them will be motivated to modify the product or spend time and money to develop a home-built version that exactly satisfies their needs.16 A well-known historical example of this phenomenon was the Model T Ford, which was produced and sold in only one type. Users engaged in massive modification activities to make this car a better match with their personal needs. In fact, Model Ts were modified to form both snowmobiles and tractors, and these modifications were sold as do-it-yourself kits at the time.
Note that manufacturers may have good reasons not to invest in tailor-made products. User segments may be too small for commercial viability, or companies may just overlook an opportunity if it’s not easy to spot. Nevertheless, industries characterized by heterogeneous customer preferences and many peripheral segments are more likely to contain innovative user communities and businesses founded by former consumers.17
Opportunity or Threat?
Innovative user communities do not necessarily pose a threat to existing companies already doing business in an industry. In nascent industries, user communities, in effect, reveal features commercial products are still lacking, and proactive companies with relevant capabilities and/or similar products may take advantage of this and step in. In existing industries, users may also develop complementary innovations that increase the value of an existing manufacturer’s current products. Both potential roles of innovating user communities are discussed next.18
Competing Innovations User communities may develop direct alternatives to the products of existing companies that are cheaper or more suitable to their personal needs. Such innovation alternatives are more likely (but not necessarily or exclusively) found in industries in which some potential users are not yet served. As real-life examples such as Linux demonstrate, the existence of user-developed competitive innovations does not imply that existing companies in the industry will be wiped out. Potential users of the product developed by the user community may face high adoption costs, so that a product ends up being available either via a peer-to-peer channel (in other words, through a user community freely revealing a design) or the traditional marketplace (in other words, through companies with commercial offerings).
The current situation in 3-D printing is an example of this dynamic. It takes time, skills and effort to build a RepRap, and the self-assembled printer typically breaks down from time to time. Printer kits sold by user-founded businesses are better in this respect but still require skills to build and maintain, so some users prefer a traditional commercial product made by an established business.
The presence of competitive user-developed innovations has two types of implications for existing companies in that industry.19 On the one hand, such innovations decrease users’ willingness to pay for a commercial product, so price discipline is imposed on existing companies. Not surprisingly, we currently see that existing 3-D printing manufacturers are offering their products at increasingly lower prices. On the other hand, existing companies may benefit from user-developed competing innovations that are potentially commercially attractive. These innovations identify what is currently missing in commercial products, and companies may just adopt these designs and further improve them to offer better products, realize cost savings and so on. Thus, innovating users are a source of free ideas and prototypes that can enhance a company’s offerings.
Complementary Innovations User communities can also create products that are essential or useful complements to existing companies’ offerings. In such cases, user communities may well increase existing companies’ profit potential. Complementary innovations are more often found in industries where some users are not adequately served. For example, toolkits were sold to modify a Model T Ford into a tractor, and this enhanced Ford’s revenues.
Complementary innovations by user communities are found in 3-D printing, too. The 3-D printing user community, for example, delivers content for Thingiverse, a community website that allows anyone to post his or her CAD designs, which other users can then download, modify and print. Likewise, users have developed easy-to-use CAD modeling software, which has been further refined by user-founded businesses. While early RepRap enthusiasts needed to master professional CAD software, today they can generate input data by medical scanners, entertainment software and simple drawing and sketching programs. These complementary tools have increased the general value of lower-end 3-D printers to consumers — regardless of whether those 3-D printers are open-source or based on a manufacturer’s proprietary design.
Five Ways Existing Companies Can Respond
To respond to innovative user communities, existing companies have a range of options, and they may be applied in parallel. Five strategic responses include: (1) monitor, (2) attack, (3) adopt, (4) acquire, and (5) facilitate.20
1. Monitor Whatever the industry, it never hurts an existing company to keep track of what user communities are doing — so that one can react or appropriate what is observed. Close monitoring enables existing companies to make more accurate sales forecasts and optimize their supply strategies. In 3-D printing, for example, lower-end manufacturers keep track of how the RepRap and derivative commercial machines are evolving, and most of them have employees who build these machines, either as part of their jobs or in their leisure time.
If user communities develop potentially competitive products, existing manufacturers should be concerned with understanding users’ adoption costs and the size and growth of the do-it-yourself community, which need to be accounted for in their own pricing strategies. Moreover, user communities’ innovation activities may inform existing manufacturers about their own products’ weaknesses, which they can then address in subsequent product development and product improvement.
To monitor user innovation effectively, companies need to be able to identify users who are innovating. What’s more, because prior research has found that the majority of consumer innovations are not adopted by others,21 companies need rules of thumb to identify which user innovations have the most potential to be seen as useful by others and spread.
In the RepRap community, many innovations are developed, but only a few prove generally useful and are therefore picked up by many other community members. To explore the determinants of innovation and its diffusion in this community, we organized a Web survey. (See “About the Research.”) We identified rules of thumb regarding what kinds of community members are likely to innovate and which of their innovations are most likely to be adopted by others.
We found that RepRap community members are more likely to innovate the more they are experienced with building 3-D printers, maintain face-to-face contact with other community members and focus their 3-D printing time on developing improvements. Innovators also report that they have better technical skills; they spend more time on 3-D printers overall but are less likely than other community members to spend time on building or fixing their machine. (See “Who Innovates in Open-Source 3-D Printing?”) In other words, experienced “village elders” who are well-connected to other members are more likely to innovate than the average RepRap community member.22 They are more familiar with the technology and probably also more expert than newbies, and they may enjoy better access to information that can be recombined to create an innovation.
But not all user innovations are alike. Some innovations are adopted by other community members, and those are likely to be of most interest to existing companies, because they have already demonstrated some general appeal. Our survey found that, in the RepRap community, innovations are more likely to be adopted by other community members if they are freely revealed by the innovators, are easy to adopt and are concerned with software rather than hardware. (See “When Do Innovations in Open-Source 3-D Printing Spread?”) Innovations are also more likely to spread if they are developed by members who are well connected within the community and who allocate more of their 3-D printing time to printing objects and/or using their printers.
Those users who spend much time trying to innovate are, not surprisingly, more likely to innovate, but interestingly, their innovations do not have a better chance of being adopted by others. Simultaneously, those spending their time using the machine are not more likely to innovate, but if they do, their innovations are more likely to be picked up by other users.
2. Attack Another strategy existing companies may consider is attacking innovating user communities, which might seem viable in cases where users infringe upon a company’s patents. In some instances, such a response makes sense — for example, if users modify a company’s product in an undesired way, such as to create a weapon. In general, however, bringing individual users to court is not likely to be effective. While direct competitors can be sued, fighting thousands of individuals around the globe is usually impractical, not beneficial in terms of revenues and potentially harmful to the company’s reputation among customers. Attacking users may well escalate into a conflict in which users appeal to higher principles and inflict substantial damage.23 In 3-D printing, system manufacturers have so far refrained from bringing individual user community members to court. This might change if user-founded companies become increasingly competitive, or set a new industry standard, but existing manufacturers should still be aware of potential negative reactions.24
3. Adopt In some instances, companies will want to adopt or copy the technologies, methods or improvements developed by user communities. These can generally be obtained for free, as many innovators in user communities do not protect their contributions with patents. In 3-D printing, incorporating community innovations is an almost routine practice. For example, Delta Micro Factory Corp., based in Beijing, China, introduced an extrusion-based portable printer called UP! at the lower end of the market which incorporates some of the innovations developed by the RepRap community. Likewise, user-founded businesses like Makerbot and Ultimaking still intensively collaborate with the communities from which they emerged, regularly incorporating community innovations in their newest releases.
4. Acquire Companies may absorb relevant knowledge and skills from user communities via individuals in the community. Key community members may be recruited to join a company and/or accept to collaborate with a company. Existing companies may also acquire startups founded by community members in order to get a foothold in an emerging market. Such initiatives make particular sense when user communities develop innovations that could compete with a company’s products. In 3-D printing, some existing system manufacturers have engaged in quite proactive acquisition behaviors. For example, 3D Systems bought the user-founded venture Bits From Bytes in October 2010. As Bits From Bytes offers low-cost, extrusion-based systems based on the RepRap design, this gave 3D Systems a foothold in the hobbyist and educational marketplace. In addition, 3D Systems has been active in acquiring service providers.25
5. Facilitate Existing companies may also seek to influence the direction and nature of the efforts of user communities. This option may make particular sense when communities develop innovations that are complementary to, rather than competitive with, a company’s existing products. The more individuals are able to contribute and use these complements, the more customers there will be for the company’s own commercial products. Accordingly, companies may want to stimulate the emergence of such user communities and facilitate their innovation and sharing activities. This can be done by methods such as online toolkits that facilitate user innovation and product modification, contests and awards, or sponsoring websites or key community members’ contributions.
When companies try to influence user communities, they first need to understand why community members participate in the community. LEGO’s experience with its user communities, for example, suggests that companies should not just focus on getting a job done, but rather recognize that users’ needs are different from those of employees, and intrinsic rewards (recognition, social bonding, fun) generally may be more helpful than money in motivating users. Moreover, community members often do not like intellectual property protection. The potential tension is that a company often would prefer that users freely provide their ideas, prototypes and/or solutions for feedback and further improvement by the company, but on the other hand, the company would like to keep knowledge within its own doors in order to protect it.26
The emergence of open-source 3D printers illustrates how quickly high-tech markets can be changed by innovative, collaborative users and the companies they form. And, as the case of 3-D printing shows, emerging user communities offer lots of opportunities to existing producers — as well as competition.
What’s more, we believe that innovation by user communities will be increasingly seen in more industries in the future. This is due to several exogenous trends, including increased understanding of modular design practices, decreasing design and collaboration costs thanks to cheaper and more capable computerized design tools, decreasing communication costs thanks to the Internet, and increasingly better educated populations of citizens across the globe. These same advances also diminish the costs of innovation diffused via peer-to-peer networks. Indeed, these factors are all drivers behind the emergence of open-source 3D printing, but they will also affect other industries in the future. Smart companies should start rethinking their innovation management practices accordingly.
1. In newspapers and magazines, 3-D printing has been described enthusiastically as everything from “the technology that could re-shape the world” to “one that is about to transform every single aspect of our lives.” See, for example, S. Richmond, “3D Printing: The Technology That Could Re-Shape the World,” The Telegraph, July 28, 2011; and H. Lipson, “3D Printing: The Technology That Changes Everything,” New Scientist, July 30, 2011, p. 20.
2. C. Anderson, “Makers: The New Industrial Revolution” (New York: Crown Business, 2012): 14.
3. N. Gershenfeld, “How to Make Almost Anything: The Digital Fabrication Revolution,” Foreign Affairs 91, no. 6 (November-December 2012): 43-57.
4. T.T. Wohlers, “Wohlers Report 2012: Additive Manufacturing and 3D Printing State of the Industry, Annual Worldwide Progress Report” (Fort Collins, Colorado: Wohlers Associates, 2012). This annual report elaborates substantially on the 3-D printing industry, technologies and trends.
5. Ibid., p. 125 and 131.
6. Ibid., p. 133. See also “Stratasys and Objet Complete Merger,” Stratasys press release, December 3, 2012, http://investors.stratasys.com/releasedetail.cfm?ReleaseID=724378.
7. Ibid., p. 65 and 256.
8. E. de Bruijn, “On the Viability of the Open Source Development Model for the Design of Physical Objects: Lessons Learned From the RepRap Project” (master’s thesis, Tilburg University, 2010).
9. Wohlers, “Wohlers Report 2012,” p. 137.
10. C. Baldwin and E. von Hippel, “Modeling a Paradigm Shift: From Producer Innovation to User and Open Collaborative Innovation,” Organization Science 22, no. 6 (November-December 2011): 1399-1417.
11. P.B. Meyer, “Open Technology and the Early Airplane Industry” (presented at the Economic History Association 2012 Annual Meeting, Vancouver, Canada, Sept. 21-23, 2012).
12. E. von Hippel, S. Ogawa and J.P.J. de Jong, “The Age of the Consumer-Innovator,” MIT Sloan Management Review 53, no. 1 (fall 2011): 27-35.
14. A. Afuah, “Innovation Management: Strategies, Implementation, and Profits,” (Oxford: Oxford University Press, 2003).
15. S.K. Shah and M. Tripsas, “The Accidental Entrepreneur: The Emergent and Collective Process of User Entrepreneurship,” Strategic Entrepreneurship Journal 1, no.1 (November 2007): 123-140.
16. E. von Hippel, “Democratizing Innovation” (Cambridge, Massachusetts: MIT Press, 2005).
17. For an extensive discussion, see Shah and Tripsas, “The Accidental Entrepreneur.”
18. Industries can be characterized as user-contested and/or user-complemented markets. The nature and microeconomic effects of innovating users in both types of markets are discussed by C. Raasch and E. von Hippel, “Modeling Interactions Between User and Producer Innovation: User-contested and User-complemented Markets,” working paper (June 2012). See http://ssrn.com/abstract=2079763.
19. For a detailed discussion, see Raasch and von Hippel, “Modeling Interactions.”
20. These strategies were partly identified by S. Flowers, “Harnessing the Hackers: The Emergence and Exploitation of Outlaw Innovation,” Research Policy 37, no. 2 (March 2008): 177-193.
21. See von Hippel, Ogawa and de Jong, “The Age of the Consumer-Innovator.”
22. A similar finding was reported by L. Dahlander and L. Frederiksen, “The Core and Cosmopolitans: A Relational View of Innovation in User Communities, ” Organization Science 23, no. 4 (July-August 2012): 988-1007.
23. E. Mollick, “Tapping into the Underground,” MIT Sloan Management Review 46, no.4 (Summer 2005): 21-24.
24. 3D Systems recently sued Formlabs, a new venture offering a home use system printing high-resolution metal parts. See www.3ders.org/articles/20121121-3d-systems-files-patent-infringement-lawsuit-against-formlabs-and-kickstarter.html. Although Formlabs did not originate from the RepRap community, the case is also marked by negative responses from home users: see http://lucept.com/2012/11/24/3d-systems-suing-kickstarter/, accessed on November 28, 2012.
25. See Wohlers, “Wohlers Report 2012,” p. 118.
26. Y.M. Antorini, A.M. Muñiz and T. Askildsen, “Collaborating With Customer Communities: Lessons From the Lego Group,” MIT Sloan Management Review 53, no. 3 (spring 2012): 73-79.