Patent Assignment
What Do You Need to Know About It?

The patent assignment - if you look at the cover sheet of a patent you will notice that many of them have inventors listed and also an assignee. So what does patent assignment mean?

A patent has many of the attributes of personal property. So the owner can assign the legal rights of the patent to another. This is done with a formal legal document.

For U.S. citizens this is normally accompanied by a certificate of acknowledgment by a person authorized to administer oaths - i.e., a notary public. This assignment should then be recorded in the US Patent and Trademark office. The requirements may be slightly different in various foreign countries.

Legal Rights

So what are these legal rights of the patent that are assigned? You may recall from our articles on the rights of a patent that ownership of a patent gives the patent owner the right to exclude others from making, using, offering for sale, selling, or importing into the United States the invention claimed in the patent. But ownership of the patent does not automatically give the owner the right to make, use, offer for sale, sell, or import the claimed invention because there may be for example, a dominating patent or other legal constraint that prevents that. It is only the right to exclude that is the patent right.

This then is what is transferred in a patent assignment - this right to exclude.

A patent assignment can get complicated. It can be the transfer of a your entire ownership interest or a percentage of your ownership interest in the patent or application.

So How Does This Differ From Licensing?

Unlike a patent assignment, the licensing of a patent transfers a bundle of rights which is less than the entire ownership interest. These rights may be limited as to time, geographical area, or field of use. A patent license is a contractual agreement that the patent owner will not sue the licensee for patent infringement if the licensee makes, uses, offers for sale, sells, or imports the claimed invention, as long as the licensee fulfills its obligations and operates within the bounds delineated by the license agreement. Licensing agreements can get very complicated and you should use an experienced licensing attorney to draft it.

An exclusive license may be granted by the patent owner to a licensee. The exclusive license prevents the patent owner (or any other party to whom the patent owner might wish to sell a license) from competing with the exclusive licensee, as to the geographic region, the length of time, and/or the field of use defined in the license agreement.

A license is not an assignment of the patent. Even if the license is an exclusive license.

What About Joint vs. Individual Ownership.

This can also get complicated. Either an individual or joint entities may own the entire right, title and interest of the patent . There are at least three possibilities - 1) there can be multiple inventors; 2) there can be multiple partial assignees; or 3) there may be a combination of 1) and 2). Each individual inventor may only assign the interest he or she holds; thus, assignment by one joint inventor renders the assignee a partial assignee. A partial assignee likewise may only assign the interest it holds; thus, assignment by a partial assignee renders a subsequent assignee a partial assignee. All parties having any portion of the ownership in the patent property must act together as a composite entity in patent matters before the Office.

The cleanest agreement is of course when all inventors jointly assign their patent rights to one entity. The options more complicated than that can lead to "Excedrin" assignments. Again - you need a good contract attorney to handle that.

Recording the Assignment

There are two ways to record the assignment of a patent with the US Patent Office. The first is to record it in the assignment record of the US Patent Office. This is straightforward and can be done online. This is strictly what is known as a ministerial act; it is not an Office determination of the validity of the assignment document. The second approach is to make the assignment of record in the file of a patent application - this is necessary to permit the assignee to take action in the patent proceeding.


Let me remind you - do not use the above for formal legal advice. If you have a complex assignment question you should get the advice of a contract attorney experienced in patent matters. See my Liability Disclaimer on the Nav Bar.

And if you would like to read the official word on Assignment from the MPEP - you can read 35 USC ยง 261 here.


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Mike Ervin
Mike Ervin - Cost Effective Small Business Patent Protection.

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