Brought to you buy Colorado patent attorney Mark Trenner

patent attorney
The most common patent is the “utility” patent, which, in the United States is effective for a period of 20 years from the date of filing (unless it was filed before1995, in which case it is effective for 17 years from date of issue, or 20 years from date of application, whichever is later).  You can also apply for a “provisional” patent which is less expensive to file than a utility patent.  However, the protection last for only one year, after which time you must file for the more common patent.  Provisional patents are seen as a cost effective way to get a grace period before filing for a non-provisional patent.  This will allow the inventor some time to market their invention before incurring the cost of a non-provisional patent.
There are some other types of patents not as common:
A “design” patent only protects a new, original ornamental shape and appearance of a specific class of objects (such as shoe treads, perfume bottles, household appliances), and only for a limited time of 14 years from date of grant.
A “plant” patent covers a new and distinct, asexually reproduced species of plant, for the same period of years as for a utility patent (i.e., 17 or 20 years). Some forms of patents have periodic payments after they are issued, and they can not be enforced if they lapse.

What is a patent? Part 3