Is software patentable?

This page discusses that very current and, it must be said, oft-controversial, question.  My aim here is to address the facts, and not the controversy.  I have provided some basics concerning how to obtain a software patent, as well as some considerations in the event you have been accused of infringing a software patent.  My standard disclaimers apply here, including that nothing on this page should be taken as legal advice, and if you have a software patent question, or are considering a software patent application, you should consult a lawyer.

Is software patentable?

My own answer is that yes, here in the United States, software remains resoundingly patentable, even though patent examiners regularly tell me something along the lines of “software per se is not patentable.”  (Business methods, we would need to discuss — probably not so much.)

In June, 2010, the U.S. Supreme Court issued its much-awaited decision in the case of Bilski v. Kappos.  In terms of clarity, the wait was not so worth it.  The patent claim at issue in Bilski, directed to a method of hedging risk in commodities transactions, was what one might call a “pure” business method.  Almost no one expected the Supreme Court to hold that the claim was valid, and almost no expectations were disappointed.  The big question in advance of the Bilski decision was the extent to which the Court’s opinion would lead to findings that other kinds of claims, particularly software claims (and some claims to bio-tech inventions) were unpatentable.

Unfortunately, long after Bilski, the question of its scope remains somewhat unanswered.  However, some general themes are emerging.  Can your claim be practiced entirely within the human mind, or with pencil and paper?  Then it is not patentable.  Is the claim directed to hardware or some physical structure?  Then it is patentable.  And then we enter the grey zone.  Does the claim include physical elements, like a computer to execute claimed method steps?  In that case, the claim can probably be drafted in such a way as to pass the scrutiny of the Patent Office.  Whether a Court will find such a patent valid in five or ten years is harder to predict, and probably depends on the specific elements being claimed.

How to Obtain a Software Patent

Patent Basics

Certain basic rules for obtaining any patent apply in the case of a software patent application.  Your invention needs to be novel and non-obvious, i.e., neither taught nor suggested by what we patent lawyers call “prior art.”  You cannot have sold or offered for sale, or publicly displayed, your invention more than a year before filing an application for patent.  No one else can have invented what you are claiming before you did.  So, to paraphrase Monty Python, if you feel you have something new and completely different, and that something has commercial value, then you should think about a patent application.  (You should be aware that some of what I say in this paragraph is going to change under the America Invents Act, which President Obama signed into law in September, 2011.)

Patent or trade secret?

A question that commonly arises when considering whether to file a a patent application directed to software is whether the subject matter of the patent application would be better preserved as a trade secret.  Although it is possible to file patent applications in the United States that do not become public, at a minimum, if and when you get to the point of having a patent issue, the patent is published for the the world to see.  If you have invented an incredible algorithm that cannot be discerned without access to your confidentially maintained source code, then consider whether keeping that algorithm secret might be more valuable than a patent.  On the other hand, if any user of your software will immediately discern your novel and valuable feature, then a patent application probably offers you the best protection.

Patent or copyright?

People sometimes ask why they should consider a software patent application when a copyright registration for software is so cheaply and easily obtained.  The answer is that patents and copyrights protect different aspects of software, and are in fact complementary.  Moreover, patent protection is generally much broader, and much more valuable, that copyright protection.  It is often said that a patent protects an idea, while a copyright protects the expression of the idea.  Thus a patent can protect your novel algorithm regardless of how a programmer implements the algorithm.  A copyright only protects a particular expression, that is, a particular implementation, of the algorithm.  All of this is a gross over-simplification, but you get the idea.  Patents can confer a lot of benefit unobtainable by copyright.

Do I have patentable subject matter?

I covered this above, but include the question here because it is one every software patent applicant should consider.  As I said, today, right now, I think it is generally possible to craft software claims that will survive the Patent Office’s scrutiny.  And it is possible to craft claims responsive to what appear to be trends in the courts that have been weighing in on the patentable subject matter question.  But you need to know that the law in this area is in flux.  The possibility that you may claim subject matter that is ultimately deemed not patentable under the law should not, in my view, usually be a deterrent.  But it is a further risk factor to consider.

What is the process for obtaining a software patent?

First, you need to prepare and file a patent application with the United States Patent and Trademark Office (or with a foreign patent office, but I am not going to go into detail about that here).  Legally, you can do this yourself.  However, having been a patent examiner and having seen inventor-written patent applications, I would not recommend filing a patent application, especially for software, without a registered patent agent or attorney.  Patent-application drafting presents a lot of pitfalls.  Your patent claims need to not only be properly written, but properly supported by the rest of your application.

After you file the application, you then wait for the Patent Office to act on it; backlogs of 18-36 months are not uncommon.  And then, when the Patent Office does act, they usually issue what is called a rejection.  A rejection is just what it sounds like.  However, don’t lose heart.  While there are patent applications that just don’t make it through the process, most issued patents were initially rejected by the patent examiner.  By amending claims and/or presenting arguments to the examiner, it is often possible to overcome rejections.  This back-and-forth with the patent examiner is called patent prosecution.  Hopefully, at the end of the process (which sometimes can involve an appeal of the examiner’s decision), you receive a patent.

What good is a software patent?

Another legal truism is that a patent confers the right to exclude others from practicing your invention.  If you obtain a patent that would be valuable to your competitors, or others, you can license your patent for royalties, or even attempt to have infringers enjoined from practicing your invention altogether (although the bar is pretty high for this).  The bottom line is that, if your invention is valuable, patenting your invention can provide an important tool for enhancing and leveraging that value.

Software patent defenses

The bad news is that patent litigation is notoriously expensive.  That said, even if you have been sued, you have options. If you are simply accused of infringement, or perhaps are merely aware of a patent that may cause concern, you have even more flexibility.  Here is a non-exhaustive list of issues to consider.


Infringement of a software patent can be difficult to prove, sometimes requiring detailed and complicated journeys through source code.  Sometimes patent owners will accuse software of infringing without having performed a full analysis, which most courts permit the patent owner to do.

Thus, sometimes (not always, or even often, but sometimes), a well-reasoned and not-too-subtle non-infringement argument can cause a patent owner to think twice about moving forward with an infringement claim, or even to back down.  In any event, when faced with a software patent, your first step should be to evaluate your infringement defenses.  How strong are they?  Do they depend on a construction of the patent claims that a court may not adopt?  Are your arguments so clear that the patent owner will have to think twice?


Proving a patent claim invalid in court is an uphill climb for a defendant, although it has often been done.  Many of the patents that have been most famously asserted against various Internet technologies have been difficult to invalidate because they have early priority dates, but again, it has been done.  To invalidate a patent using prior art, the defendant must prove (by a high evidentiary bar) that prior art demonstrates each and every element of the patent claim.  Patents can also be invalidated by evidence of prior public sales, use, or offers for sale.  While the Internet has spawned a lot of patent litigation, it is also a valuable tool for finding evidence of invalidity.

It is also possible to ask the Patent Office to reexamine an issued patent.  (Moreover, so-called post-grant proceedings are being expanded under the America Invents Act.)  My own experience with reexams is mixed, which is to say that sometimes I have seen it be a valuable tool.  Reexams are also generally much less expensive than litigation, making them attractive to many parties.  Further, depending on the circumstances, many courts will stay litigation while reexamination proceedings are pending, further adding to the value of reexaminations as a strategic tool.