Demon wanted to be sure to do everything he could to protect his technology. On his original patent, he had to define his product in detail-with a list of features for his main claim. He also had a variety of additional, or secondary, claims. "Secondary claims continue to define an invention with increasing specificity," says Kelly. "If a patent is challenged in court, a judge might find that certain claims are invalid and the patentability "line" will fall somewhere between the broadest and narrowest claims." In other words, secondary claims can narrow the scope of a patent's protection.
Demon's strategy was to patent many different variations of the shoe to get broad coverage. His original patent had 15 claims. Demon also has several additional patents pending that would cover even more options on how his technology could be produced. Demon's aim is to patent every manufacturing option so that a competitor can't design around his patent. Demon's strategy isn't as effective as getting a patent with a broad claim, but it can come pretty close if Demon is able to identify every possible design configuration.
The drawback to this strategy is the cost-the first three claims are free, but each claim after that will cost you $39 (unless you have 21 or more claims, in which case they're $9 apiece). That's on top of the $345 filing fee for a utility patent. Then there are patent attorney fees, which could easily run $15,000 or more. But in Demon's case, that money is a fraction of what he might earn on licensing agreements. Demon's already signed a deal with major retailers in southern California to distribute his shoes, further pumping his product's value. So if you're going to make the investment in a patent, be sure to get one that provides meaningful protection. If you can't get a patent with a broad claim, try to sew up the idea by patenting as many product variations as possible.