As most engineers know, the U. S. patent system is intended to protect the inventor's rights in an invention. A patent holder has exclusive rights to make, sell, or license an invention for a limited period of time (currently 20 years).

This is a compromise between two extremes: the free-for-all extreme in which no patent law exists and anyone who can figure out an invention can copy it and make it without incurring development costs, and the perpetual-monopoly extreme in which patents would last forever and nobody else could ever make the invention.

Most compromises need adjusting as circumstances change, and patent law is no exception. According to U. S. Senator John Cornyn of Texas, one of the worst current problems in patent law is the growing number of so-called "patent trolls." Who qualifies as a patent troll? It probably depends on who you ask.

If you ask someone at Apple Computer, which is named as the defendant in more cases filed by patent trolls than any other U. S. firm, Apple will probably tell you that a patent troll is a person or organization that acquires a patent solely for the purpose of suing a deep-pocketed firm such as Apple.

For that matter, any patent is nothing more than a license to sue. This is because, at least in the U. S., patent infringement is a violation of civil law, not criminal law. But with full-blown patent infringement cases complete with a jury costing upwards of $1 million, and current laws that allow the plaintiff to conceal the details of the accusations until later in the legal process, the defendant named in a patent troll's lawsuit usually has only two choices: (1) call the plaintiff's bluff and go to trial, knowing you might lose, and even if you win it will cost you a megabuck or more, or (2) settle out of court without seeing the details, and write off the six-figure settlement expense as just a cost of doing business.

Of course, patent trolls may view the situation differently. Some legitimate inventors do not have the financial backing to found a company in competition with one of the big boys, and patent litigation may be their only hope of profiting from their invention. But if an individual or group clearly has no intention of making or using the patented item, and is formed for the sole purpose of pursuing patent litigation based on dubious claims, you can be fairly sure you are dealing with a patent troll.

Sen. Cornyn's proposed changes would move the law in what he thinks is a fairer direction. For the first time, plaintiffs (i. e. patent trolls) would have to reveal their accusations up front in enough detail so that the entity being sued could make an informed decision as to the likelihood that a full-scale lawsuit would succeed. With this and other changes, the hope is that frivolous and baseless patent suits that amount to little more than legalized blackmail would disappear from court dockets, while leaving the more substantial cases in place.

Like any change in the law, the proposed legislation may have unintended consequences. But to find out what they are, we'd first have to pass it into law. Somewhat surprisingly, the ideas behind the Republican Sen. Cornyn's proposal have been endorsed by President Obama, and Cornyn cites the U. S. Senate as the main roadblock, which under the control of the Democratic Party has so far not acted on the legislation. We have noted the sclerotic state of Congress elsewhere, and will simply express here the hope that the Senate will do the right thing and pass Sen. Cornyn's legislation, if it will do as much good as he says it will.

One advantage to doing a blog for a long time (we observed our eight-year anniversary a couple of weeks ago) is that you can note long-term trends, and call for changes, and actually see them happen after a while, sometimes. Back in 2006, the first year of this blog, I discussed a patent issue not entirely unlike the current one of patent trolls: the situation of "submarine patents."

Until 2000, the content of a patent filing was a deep secret between the person who filed the patent application and the U. S. Patent and Trademark Office. The secret was revealed to the public at the end of the process, only after the patent was issued, so some inventors became skilled in intentionally delaying the granting of a patent in order to keep it secret until its contents became something valuable. Then, the patent submariner would allow the patent to issue and try to sue the pants off some large firm that was profiting from a technology at least remotely related to the now-surfaced patent.

According to Wikipedia, one of the most skilled practitioners of this art was an independent inventor by the name of Jerome H. Lemelson. Lemelson was without question a clever and legitimate inventor, who clearly began his career as a fruitful developer of original ideas which he licensed to various firms, mostly in the areas of machine vision. But as time went on, he developed habits which his critics began to describe as filing for submarine patents, although Lemelson always denied the accusations. He also became very wealthy, and after his death his estate contributed to the formation of the Lemelson Foundation with the purpose of encouraging invention and innovation by individuals.

The Foundation's National Collegiate Inventors and Innovators Alliance (NCIIA) sponsors competitions and grants to teams of college students and faculty members interested in developing inventions, and has no doubt done a lot toward encouraging such activities over the years since Lemelson's death in 1997. As Lemelson no doubt intended, any bad memories or ill will created by his patent litigation activities during his lifetime are fading in the light of the good his money is doing after his passing.

As it happened, when I wrote about submarine patents in 2006, they were already passing from the scene, because in 2000 the Patent Office began revealing the contents of most applications no longer than eighteen months after filing. So it is no longer possible to do the submarine-patent dodge today, at least in the U. S.

If he were still around, Lemelson might not like the tone of Sen. Cornyn's proposed changes to patent law. Lemelson always sided with the underdog in a patent fight, and anything that would tend to make the independent inventor's lawsuits harder to prosecute against major firms is something he would probably oppose.

But law is inherently a balancing act, and if the U. S. Senate sees fit to pass the anti-patent-troll legislation, maybe in another eight years I can look back and see how well it did what it was supposed to do. But don't hold your breath.

Sources: Sen. John Cornyn's editorial "It's time to stop patent abuse with bipartisan Senate support" appeared in the Mar. 15, 2014 edition of the Austin American-Statesman. I referred to Wikipedia articles on Jerome H. Lemelson, submarine patents, patent trolls, and the term of U. S. patents. The NCIIA website is

This column originally appeared on the Engineering Ethics blog, you can find it by visiting