Unity of invention

You filed one application describing three related things. The examiner says that is three inventions and you may only pursue one.

In simple words

The requirement that a single application relate to one invention, or to a group of inventions linked so as to form a single inventive concept.

Think of it as

One application, one inventive idea.

Why it matters

A unity objection is not fatal - it usually means filing a divisional application for the parts you cannot pursue in the parent. But divisionals must be filed before grant of the parent, so a unity objection creates a deadline you have to notice.

A simple example

An application claims a new catalyst, a process using it, and an unrelated reactor design. The examiner objects; the applicant elects the catalyst and files a divisional for the reactor before the parent is granted.

Common mistake

Ignoring a unity objection until after grant. The chance to file a divisional closes when the parent is granted.

Where it comes from

Patents Act 1970, section 10(5) and section 16; Patents Rules 2003, rule 13(2A) as inserted in 2024