Writing a lot does not always lead to a strong patent right.
At the same time, a short patent specification is not necessarily a bad one.
The Role of a Patent Specification
Claims define an invention.
The role of the patent specification is to explain in detail the invention defined in the claims.
Because claims define the scope of the patent right, every word matters.
The wording of the claims determines how broad or narrow the right will be.
To allow a wider interpretation, claims are often written in an abstract way.
This is the most critical part, and it often goes through many rounds of revision.
The patent specification describes specific ways to carry out the invention, called “embodiments.”
These descriptions are concrete and practical.
Because claims are abstract and the patent specification is concrete, they are written in completely different ways.
In a patent specification, you are not required to write only about the invention defined in the claims; you may also freely describe matters that are only weakly related, or even unrelated.
There is no word limit. You do not have to write a lot.
The Benefits of Writing a Longer Specification
The main benefits of writing more in a patent specification are listed below.
(1) A Higher Chance of Obtaining a Patent
Anything written in the specification can later be added to the claims.
In this sense, the specification works as a collection of materials that can be used to shape the claims.
Depending on the examination process, it may be necessary to slightly adjust the definition of the invention.
If the specification contains many useful materials, it becomes easier to make such adjustments and obtain a patent.
(2) Easier to File Divisional Applications
Based on the contents of the specification, it is possible to file divisional applications later.
A divisional application is a separate patent application derived from the original one.
As with point (1), if the specification is rich in content, many patent applications can be created from a single original application.
(3) Lower Risk of Rejection for Insufficient Disclosure
Patent law requires that the invention be sufficiently explained in the specification.
If the explanation is insufficient, the patent will not be granted.
Writing a lot does not automatically guarantee compliance, but in general, a very short specification is riskier than a reasonably detailed one.
(4) Preventing Others from Obtaining Similar Patents
If certain technical ideas are already disclosed in your specification, others cannot obtain patent rights for similar inventions later.
Some patent applications are filed mainly to prevent competitors from obtaining patents.
Downsides of Writing a Long Specification
The main disadvantages of writing a long patent specification are as follows.
(1) Higher Costs
In general, a longer specification leads to higher attorney fees.
When filing abroad, translation costs also increase.
In some countries, official fees increase as well.
(2) Greater Burden of Review
Writing long documents is hard, but reading them is also hard.
Checking for typos, consistent terminology, and logical consistency takes more time and effort.
(3) Disclosing Too Much Information
This is the flip side of advantage (4).
By disclosing too much, competitors may better understand your company’s development direction.
There is also a risk of giving others hints for their own technical development.
For example, experimental data may help satisfy disclosure requirements, but it may also reveal valuable information.
Other Factors That Affect the Length of a Specification
There are also other factors that influence how long a patent specification should be.
(1) Requests from the Inventor
Because an invention reflects the inventor’s passion, there are matters that the inventor, or the IP department, wishes to have included.
Even if something seems unnecessary at first, it may become useful later.
If a part reflects the inventor’s strong interest or commitment, it is often worth writing.
(2) Making the Invention Easier to Understand
To help examiners and other readers clearly understand the invention, it may be necessary to explain matters that are already common technical knowledge in the field.
For complex technologies, technical explanations naturally become longer.
(3) Customs and Preferences
There are industry-specific and client-specific customs regarding the length and style of patent specifications.
In long-established technical fields, there are proven styles that are considered more likely to lead to granted patents or effective enforcement.
Some people feel comfortable only with long specifications, while others prefer short and concise ones.
Experienced IP professionals may have an intuitive sense of these factors.
How deeply to explain certain points, and how broadly to cover related ideas, depends on the nature of the technology and the needs of the client.