How Do I Correct or Revise My Patent?

Obtaining a patent is a lengthy and sometimes difficult process. On average, it can take two years or more between the time of the patent filing and the issuance of the patent by the U.S. Patent and Trademark Office (USPTO), the federal agency that administers patents.

Once an inventor finally does obtain a patent, however, there are situations in which that inventor will need to make certain changes to the document. Sometimes these changes are due to an error in filing (such as mistakenly omitting the name of a co-inventor) and sometimes these changes are needed due to a substantive amendment to the invention itself. Fortunately, in most situations, inventors need not start from scratch and file a brand new patent application.

There are two main areas of amendments to existing patents that inventors might consider:

• amendments to the names of the inventors, and
• amendments to the substantive aspects of the patent itself.

How can you go about seeking these sorts of amendments?

Amendments to the Names of the Inventors

Patent holders will occasionally make mistakes when submitting the names of the inventors or owners on their initial patent application. This is particularly common in a situation where an invention has multiple inventors.

Errors like this can cause legal problems down the road if you should need to enforce your patent in federal court to defend from infringement. After all, applicants are required to list all inventors on a patent for the patent to be valid, pursuant to 37 C.F.R. 1.41(a), which requires that the application "include, or be amended to include, the name of the inventor for any invention claimed in the application."

After a patent has been issued—or even while it is still under examination—the owner may submit a Recordation Cover Sheet to the USPTO's Assignment Recordation Branch. This office will accept the documentation and ensure that your patent is updated and that proof of the update is issued to you.

The Recordation Cover Sheet can be submitted online through the Electronic Patent Assignment System (EPAS). EPAS will ask you to upload copies of your patent, as well as supporting documentation (such as an assignment of the patent).

The process for seeking amendments to inventors' names is outlined in 37 CFR Section 1.48. The section also notes that the USPTO "may require such other information as may be deemed appropriate under the particular circumstances surrounding the correction of inventorship." In other words, you should be prepared to provide a basis for any amendments that you seek, should the USPTO request additional information.

Amendments to Substantive Patent Claims

Patent owners may also apply to the USPTO for changes to the substantive aspects of the issued patent—that is, the actual claims made within the patent that form the basis for the invention. However, the key rule is that no new material can be added to the patent. New claims would need to be the subject of an entirely new patent application.

So what can be amended? According to 37 C.F.R. 42.121 and 37 C.F.R. 1.121, a patent owner may seek to amend items like the descriptions of the claims or the drawings filed with the USPTO to support the claimed invention.

More particularly, 37 C.F.R. 1.121 lists each potential area that an inventor may seek to amend. Such an amendment must be filed with the USPTO by "motion" under the rules, though it is always advisable to call the general clerk's office to ask for guidance on the best way to file your particular request.

Amendments to existing patents are not required in most cases. But such amendments can be important if you later discover an error in the way in which your claims were described, and determine a way to show those claims more clearly. Such amendments can then decrease the chance of confusion by would-be infringers and assist your defense of your patent in court, should that ever become necessary.