Patents don't matter for making a printer for your own use.
They can matter if you build a business on them, like by selling objects built using them.
Especially if they improve make your process cheaper, easier, more convenient, flat-out possible, or produce a better part. (And if there ARE cheaper, etc. ways to do it, why are you using the patented tech anyhow? B-) )
Patents in the US were about increasing innovation by making first mover advantage truump second mover advantage: Giving the little guy with the bright idea time to set up manufacturing, make back his costs, reap some benefits, and get established enough to compete with existing large companies once they expire. Without them, it was thought, the existing big guys with the infrastructure in place could quickly clone the little guy's new invention and out-compete him in the market, but they wouldn't bother until the little guy had proved it was worth the effort. This would suck the incentive out of the little guys, the big guys would have little incentive to improve, and progress would be slow-to-stalled. The short-term inhibition on others deploying the invention was seen as less of an impediment to progress than having most inventions not be deployed, or even made, at all.
The idea was to set the time limit to maximize progress to the benefit of all/the country, and make manufacturing and technology grow like yeast (ala silicon valley B-) ). Part of the intent was to bias it toward innovators and make established processes free to use, because when the country was getting started the established players were owned by foreign interests. The founders wanted the country to develop its own industry, rather than being dependent on, and sending most of the profit to, big businesses in Europe.
But the time was set for heavy manufacturing at the pace of the period. It's a horrible mismatch for, say, software: With the availability of general purpose computing platforms, able to make distributable copies at electronic speed and copyright to prevent verbatim cloning, a person or company with a new software product can go from steath-mode program development to market establishment, profitibility, and even market dominance in a matter of months, before competitors can engineer their own version. So patents aren't necessary to promote innovation, leaving just their retarding effect holding down the blaze of creativity. (Then there's open source, with its alternitive monitization and/or reward strategies. But that's a "new invention". B-) )
It seems to me that:
- The expiration of patents on stereolithography did help produce the initial explosion of new, and often inexpensive, devices and the improvements in what can be made, how accurately, and how inespensively.
- The availability of machines suitable for practical industrial prototyping - even before the cheap machine explosion - pretty much forced the high-end CAD software producers to include some form of stereolithography output format, while an open output format made the choice obvious. That's a big benefit to the toolmaker for a small effort. The availability in the high-grade commercial tools is a great synergy and helps a lot. But the hobby machines needed CAD tools and open source was already up to the task: Had the big players not gone along it still would have been done, and those big players not "with the program" would be experiencing major competitive pressure from open source tools and competitors that did provide such output.
And here's the key:
- The availabitiy of these rapid general-purpose maufacturing tools will bring (is already bringing!) software's high-speed innovation and entrepenurial models to the manufacture of physical objects. Patents could be shortened in term or reduced to "design patents" - the manufacturing equivalent of copyright - and produce a physical-product explosion comparable to the computer revolution. (Or patents, like "content" copyright, could become the tool of obsoleted established players in the suppression of the competing business models.)
Brace yourself for either the physical-manufacture ramp-up to science-fiction's "singularity" or an ongoing RIAA / MPAA / conglomerate - style legal battle.