The Right to Keep Others from Practicing the Invention
The patent owner (which may be the inventor, an applicant or an assignee) in the United States has the legal right to exclude others from making, using, selling or offering to sell an invention. It is a misconception to think that a patent gives the patent owner the right to practice the invention, rather, it is a right to keep others from practicing the invention. This is an important difference, and one that can further be explained by our patent attorneys.
An example of this is that person A invents a stool (legs plus seating surface). Person B invents a backrest (legs plus seating surface plus backrest). Person B can stop anyone from making a stool with a backrest, but person B cannot himself make a stool with a backrest, because person A has the right to exclude others from making a stool. One way to resolve this is for person B to license the rights from person A to make the stool with backrest. Alternatively, person B can sell his rights to person A.
As for how long the rights last, A utility patent term is twenty years (20 years) from the initial filing and is generally deemed enforceable from the date of issuance. A patent term may be affected by patent term extensions, terminal disclaimers, priority application filing dates and maintenance fee payments, but the twenty year rule is a great rule of thumb. On the other hand, A design patent issuing today has a term of fifteen (15) years from issuance. You will see a fourteen (14) year term on many design patents, as the rule change extending the term of a design patent from fourteen to fifteen years occurred on May 13, 2015. Thus, a design patent that issued prior to May 13, 2015 has a fourteen year term, with all design patents issued on or after May 13, 2015 have a fifteen year term.
Patents can be thought of as real estate where an owner of a parcel of land has the right to prevent the use of that land by others. Similarly, a patent gives the patent owner the right to prevent others from practicing the invention in the patent. In the example above, person A can stop person B from making a product that includes what person A has a patent on (namely, the legs plus the seating surface). On the other hand, person B can stop person A from adding a backrest, as person B has the patent on the combination.
Another similarity to real estate is that, in an analogous manner, a patent can be sold in whole or in part, a patent may be owned jointly, as well as exclusively or non-exclusively licensed. In some instances, for example, a patent may be licensed for a particular channel of trade, or particular type of customer. In other instances, a license may be geographically limited (i.e., big box sales west of the Mississippi). The variations in contracts involving patents is essentially limitless.
Such transactions can be done until the expiration of the patent, at which time, the invention enters the public domain. One thing that cannot be done is to extend a license, for example, beyond the expiration of a patent, or where a group of patents, beyond the expiration of the last expiring patent.