Can you change a patent application after filing?

Can you change a patent application after it has been filed?

Do ideas simply stop churning in your head after a patent application has been filed? Anyone creative enough to file a patent application would likely continue to think and improve upon their innovation. When your brain has been in a constant mode of creation, it would seem natural to come up with changes after a patent application has been filed. In those situations, what can you change in a patent application after it’s filed?

What parts of a patent application can be changed after the initial filing?

You can certainly amend the claims. In fact, it is quite rare to get a utility patent granted without any claim amendments. Claim amendments are part of the expected process of prosecuting utility patent applications. Be careful though. You can only amend claims to cover features adequately disclosed in your description. In other words, you cannot amend claims to add undisclosed features.

Less common are amendments to the specification. Patent rules forbid the addition of new matter once an application has been filed, so any modifications to the specification should serve to clarify or possibly delete subject matter. For example, you might be able to edit a paragraph to specify a feature that was shown in the originally filed drawings. Such textual additions might not be new matter if the original drawings adequately disclosed the features being discussed.

Be careful about amending drawings. You can add missing numerals or change numerals that are clearly typos. However, altering the substance of the figures may trigger a new matter rejection. For example, trying to change a structural component with a new component would likely be rejected.

What is considered new matter?

So modifying a product would most likely be considered new. For example, adding a new step or structure would be new matter. Replacing Component A with Component B would be new matter.

Except for editing numerals in the figures, almost any change to a drawing will be considered new matter. In rare cases, you might be able to edit or add to a drawing based on a written description that provides sufficient support for such drawing changes.

What are your options if you must change the description in a patent application?

While you generally cannot change the description in an existing patent application, you can file a certain continuing application to add new matter or make changes. Such an application is called a continuation-in-part, or simply CIP. The result is that you will have two patent applications: a parent application with an earlier filing date and a child application with a later filing date. Technically, the child CIP application will have different priority dates based on the subject matter. In the CIP, the original subject matter gets the earlier parent filing date while the new subject matter gets the later child filing date.

Why do priority dates matter? The later date of the new or changed subject matter in the CIP will make it more vulnerable to prior art rejections. For example, adding new matter in a CIP filed 10 months after the parent filing date can result in 10 additional months’ worth of prior art references that can be cited against you.

You may decide to abandon the parent application although there might be strategic reasons for keeping the parent if you can get decent claims allowed. One result is that you might end up with multiple granted patents. Owning a patent family can provide you with more options when it comes to licensing or enforcing your patent rights.

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