The high court decided Tuesday to overturn parts of a lower courtthat had limited a patent's scope. Many inventors, including those who work with tech products, feared the lower court ruling would allow copycats to rip off their products by making only minor changes.
In Tuesday's ruling in Festo v. Shoketsu Kinzoku Koygo Kabushiki, the high court gave more ammunition to patent holders by allowing them to exert a legal theory known as the "doctrine of equivalents" in certain cases.
Under the doctrine, a patent owner can assert rights that go beyond the scope of an original claim if the product performed an equivalent function. For example, if a patent owner had rights to a product that contained a copper wire, another company would not be allowed to market a product with an aluminum wire that performed the same function.
The unanimous Supreme Court ruling overturned a lower court decision that said the doctrine could never be applied to later changes a patent owner made to the application. The high court said patentees who made later changes to their applications could still invoke the doctrine to protect their patents in certain, specific cases.
Legal experts said the ruling trims the Festo decision but does not eliminate worries about copycatting.
"Although the draconian effect of Festo has been somewhat watered down, it's still a high penalty to patent holders if they don't draft patent applications correctly," said Richard Gervase, a lawyer with the intellectual property group of Mintz Levin Cohn Ferris Glovsky and Popeo.
The case started when robotics and automation system maker Festo sued Shoketsu Kinzoku Koygo Kabushiki, claiming the company infringed its patents on robotic arms parts.
On Tuesday, the Supreme Court also sent the case back to the lower court so it could apply the higher court's ruling to the Festo dispute.