Patent of addition or a separate application?

Moderate complexity - several routes or missing facts

Please review this with an advocate, patent attorney or registered patent agent before you act. Do not rely on this answer alone.

• It cannot be refused or revoked only because it lacks inventive step over the main invention or other additions to it (section 56(1)).
• It must still be new: novelty is judged taking the main specification into account (section 56(2)).
• Its term equals the remaining term of the main patent, and it ends if the main patent ceases (section 55(1)). No renewal fees are payable while it remains a patent of addition (section 55(2)).
• If the main patent is revoked, the court or Controller may, on request, order it to become an independent patent for the rest of the term; renewal fees then become payable (section 55).
• Its filing date must be the same as or later than the main application's (section 54(3)), and it cannot be granted before the main patent (section 54(4)).
• The specification must refer to the main patent or application number and state that the invention is an improvement in or modification of it (rule 13(3)).
• All other requirements, including section 3 and, for foreign filings, section 39, still apply.

Read next

• Patent of addition
• New is the easy part. Inventive is the hard part.

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