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The low-down on patents and software – and why you should care

Patentability of inventions implemented in software

The New Zealand Patents Act specifically excludes software from being patentable subject matter. However, despite the software exclusion, an invention implemented in software may be patentable. This article discusses patentability of software implemented inventions and how to determine whether the software exclusion applies.

Novelty and Inventive step

Before discussing patentable subject matter in relation to software implemented inventions, it is useful to first understand the key patentability rules applied to all inventions – novelty and inventive step.

For something to be patentable, whether it be a device or a method, it must be both novel and inventive. Novelty means the device or method is new, i.e. not publicly known prior to the day on which a patent application for the device or method is filed. This means it is essential for an inventor to keep his or her invention confidential prior to filing a patent application.

Inventive means the new device or method must not be an obvious variation or modification to what was already known. For example, the landmark case referred to in New Zealand when assessing inventiveness relates to a windsurfer. Issued in 1971, UK Patent No. GB1258317 claimed a wind-propelled vehicle including a board, a mast articulated to the board, and a Bermuda rig (triangular) sail held taunt by a wishbone boom. A windsurfer known prior to the filing date of the patent had all features of the claimed windsurfer but for having a square-rig sail instead of a Bermuda-rig sail with wishbone boom. The Court decided both sail rig types were common knowledge. Replacing a well-known square-rig sail with a well-known triangular-rig sail with wishbone boom, with all other features of the windsurfer remaining the same, was considered to be an obvious modification. The Court therefore decided the patent was invalid for lacking an inventive step.

Idea versus expression

When discussing software implemented inventions and patentability, it is also important to understand the difference between a patent right versus a copyright, or the ‘idea-expression dichotomy’.

The idea-expression dichotomy differentiates an idea from the expression of an idea. A computer program (the computer code) implements some functionality, for example a method for turning one or more inputs into one or more outputs. The functionality or method implemented by the software is the idea, whereas the actual software code is the expression of that idea. An engineer may invent a new method for controlling an apparatus. The engineer may employ a software coder to write a software program to implement the method in software. The engineer is the inventor of the method (the idea), and the computer coder expresses that idea in computer code. Of course, sometimes the same person fulfils both these roles.

The method or idea implemented by the computer program may be patentable, if it is both novel and inventive, as discussed above. The engineer can file a patent application for the method. The coder has no right to the idea and cannot file a patent application for the method, since the coder (in this example) did not contribute to or develop the method. The computer code is a copyright work and, depending on the arrangement between the engineer and the coder, the engineer may be the owner of the copyright in the code, as well as the owner of a patent application filed for the idea.

Section 11(3) of the New Zealand Patents Act 2013 contrasts two examples to help explain how patents relate to software-implemented inventions. The examples illustrate the idea verses expression concept well.

The first example is of a patentable invention; a method implemented in software for operating a washing machine in a new (and inventive) way. Since the method is novel and inventive, it is patentable.

In contrast, the second example is a process implemented in software for completing a legal document. The process involves asking questions of a user, by a computer running the software to present the user with a series of questions. The software then produces a legal document using the user’s answers to the questions. There is no novelty in this process; the process implemented in software is the same known process a lawyer uses to prepare a legal document – to ask a client a series of questions and produce a suitable document based on the client’s answers to those questions. Therefore, the idea of completing a legal document implemented by the program is not novel and is therefore not patentable.

Software implemented inventions and patentable subject matter

To successfully obtain a patent for an invention, the invention must be novel and inventive and it must be patentable subject matter. According to the Patents Act, to determine if an invention implemented in software is patentable subject matter, it is necessary to determine what the actual contribution the invention makes to the relevant field of technology.

Assessing the contribution that the invention makes essentially involves determining whether the idea that is implemented in software code is novel and inventive in view of what was already known on the day the application was filed. Consideration of how the idea addresses any problems and the advantages of doing so can be useful, and must be considered when identifying the contribution made by the alleged invention.

If we again consider the washing machine example from section 11 of the Patents Act, the idea expressed in the computer code is a new and improved way of operating the washing machine. While the only thing that is different about the washing machine is the computer program, the actual contribution lies in the way in which the washing machine works. Therefore, the software exclusion does not apply and the invention is patentable subject matter. In contrast, in the example of the computer program to prepare a legal document, the only novel aspect and therefore contribution is the computer program, which is excluded from being patentable subject matter.

If an idea expressed in software is not new or is not inventive, the inventor has made no contribution to the relevant field of technology. The only contribution the inventor has provided is a computer program, and a computer program is not patentable subject matter.

Simply automating a known process, such as in the above example of preparing a legal document, by implementing that process in a computer program to be run on a computer, likely does not make the known process patentable.

Is hardware outside of the computer running the software necessary?

Considering novelty and inventive step of an idea implemented in software does not always answer the question of whether the software implemented idea is patentable subject matter.

For example, it is possible for a software implemented idea to be patentable subject matter but to also lack novelty (and therefore not be patentable). If we consider the first example provided in

Section 11 of the Patents Act for a method for operating a washing machine – even if this method was already known and therefore not patentable, the invention is more than just a computer program, because it involves hardware in addition to the computer running the program.

However, a software implemented invention that does not involve hardware outside of the computer running the software may still be patentable subject matter. For example, a software program that causes a computer to operate in a new way or to run more efficiently and effectively as a computer is patentable subject matter. A software implemented invention may be patentable subject matter even if the only output from the program is displaying information to a user via a computer screen.

Most of the time, and certainly for ideas that have a commercial application, consideration of the novelty and inventive step of an idea implemented in software can simultaneously determine both patentability (novelty and inventive step) of the idea and whether the idea implemented in software is patentable subject matter. And in any case, consideration of whether the software exclusion applies is academic when the idea lacks novelty or an inventive step, as it is not patentable, regardless of whether or not the software exclusion applies.


To successfully obtain a patent for an invention, the invention must be patentable subject matter and it must be novel and inventive. When an invention involves an idea implemented in software, considering the novelty and inventiveness of that idea generally also answers the question of whether the computer software implementation of that idea is patentable subject matter, or in other words, whether or not the software exclusion provided in the New Zealand Patents Act applies.

Craig Rothwell is a senior associate in the Auckland patents team at James & Wells. He works with his clients to secure patent and design protection, develop filing patent strategies, and provides patentability and freedom to operate opinions. Craig has experience in a wide range of industries including building and construction, healthcare, the primary industries, and manufacturing, with a particular focus on mechanical, electrical and software-related inventions.

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