Patent Calculator


Welcome to™!  This is a free website provided by Neustel Law Offices (U.S. Patent Lawyers) to help patent attorneys, businesses and inventors determine the expiration date and maintenance fee dates for United States utility patents.  For the Expiration Date, you will have to compensate for any Patent Term Adjustment (PTA) for a particular patent which will be shown on the front page of the patent.  The Expiration Date shown below does not include any PTA or disclaimer of patent term which need to be independently verified by a patent attorney if you need to know exactly when a patent expires.  As with any important legal matter, talk to a patent attorney prior to making a determination as to when you can use a patented technology as there are no guarantees that the calculations below will be correct for a particular patent.  We hope you enjoy this useful tool.

Earliest Effective Filing Date
Application Filing Date*
Issue Date*

U.S. Patent Office Entity Size Information

Your "entity size" at the USPTO determines how much you have to pay to the USPTO in government fees for a patent application filing fee, patent application issue fee, patent maintenance fee and the like.  A "Large Entity" pays 100% of the scheduled USPTO patent fees.  However, a "Small Entity" receives a 50% discount and a "Micro Entity" receives a 75% discount off patent fees.  It is therefore important to determine whether the patent applicant qualifies as a Large Entity, Small Entity or a Micro Entity.  Below is some information to help you determine if you qualify as a Small Entity or a Micro Entity.  As always, consult with a patent attorney before deciding on an entity size to avoid mistakenly claiming an incorrect entity size which could jeopardize your patent rights.

Micro Entity Status
You can qualify for micro entity status if the patent applicant meets all of the following criteria:

     1.  Small Entity (see next section);
     2.  Not Named on More than 4 Previously Filed Applications*;
    3.  Gross Income Does Not Exceed $150,162 (based on 3 times 2011 median household income of; and
     4.  Not Under Obligation to Assign or License to an Entity With Income Exceeding $150,162.

* Applicants are not considered to be named on a previously filed application if he or she has assigned, or is obligated to assign, ownership rights as a result of previous employment. Applications filed in another country, provisional applications, or international applications for which the basic national fee was not paid do not count as previously filed application. The definition also includes applicants who are employed by an institute of higher education and have assigned, or are obligated to assign, ownership to that institute of higher education.

Small Entity Status
You can qualify for small entity status if the patent applicant is (1) individual inventors or (2) a small business having 500 or less employees.

Large Entity Status
If you do not qualify as a micro entity or a small entity, then your status at the USPTO for patent applications and patent maintenance fees will be a large entity.

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