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New Steps Determining Unity of InventionCase

published on 30 Jan 2019


The Taiwan Intellectual Property Office (“TIPO”) recently revised Volume II, Chapter IV of the Patent Examination Guidelines, which cover unity of invention, releasing the revisions at the end of 2018. New standards on the requirement for unity of invention went into effect on January 1 of 2019. With more than 70% of the paragraphs being revised, a conspicuous change is seen in the new Chapter Four regarding examples explaining the standards in determining unity of invention.

According to the Guidelines, a plurality of claimed inventions can be included in one patent application at filing if they fall under a general inventive concept, and that the claimed invention shall include one or more “identical or corresponding” “special technical feature.” A special technical feature is one that enables the claimed invention as a whole novel and non-obvious over the prior art.

When a patent has at least two independent claims, prior to performing a search, examiners are required to review whether or not the independent claims are prima facie lacking unity. If they are not, the examiners will then look into the searched prior art and identify a “specific technical feature.” The new steps detailed as follows in the Guidelines are important because they are how the examiners come to a conclusion when determining unity.

Step 1.Whether the independent claims are prima facie lacking unity.

If the claimed inventions do not have “identical or corresponding” special technical feature(s), or the technical feature(s) is merely common knowledge based on the disclosure, the independent claims are prima facie lacking unity.

Step 2.Prior art search for specific technical feature(s).

For independent claims that are not prima facie lacking unity, the examiner will perform a prior art search. Starting from Claim 1, which presumably is the claim that would have largest protective scope, the examiner will look for any special technical features. In absence of special technical features, independent claims will be deemed to not have unity.

Step 3.Whether a Special Technical Feature is found in other independent claims.

Even if a novel and inventive special technical feature is present, the examiner is required to look for an “identical or corresponding” special technical feature in other independent claim(s). If this is the case, those independent claims have unity and are eligible for inclusion in the same patent application.

Based on the revised Guidelines, however, the examiner is obligated to begin searching for another independent claim other than Claim 1 when one of the following situations occurs:

  1. Claim 1 is either directed to an indefinite invention, a non-patentable subject matter, not meeting the definition of an invention, or not industrially applicable; or
  2. Claim 1 is not the “most representative” claim in the invention (For instance if there are four independent claims respectively for a compound, a composition having said compound, a method of manufacturing said compound, and a use of said compound, the examiner shall begin the search for the compound. Or if there is no apparatus claim, the search begins from an independent method claim).

Notably, in TIPO’s search practice, if an independent claim is not considered novel or inventive, the examiner will not continue to search other groups of independent claims and their dependent claims because allegedly there is no unity. According to the revised Guidelines, the examiner is obliged to specify which claims were left unsearched due to the perceived lack of unity.

Full Search in One Payment

From the viewpoint of an applicant, a full payment for the examination fee is presumably to cover TIPO’s search service over the entire claim set in the application. But, in instances in which an examiner suspends a search owing to the perceived lack of unity of prior claims, such suspension regrettably falls short of the applicant’s expectations of the examiner to further identify the patentability of those unsearched claims.

Step 2 in the revised Guidelines shines some light to avoid an examiner’s suspension in conducting searches. Step 2 requires an examiner to begin searches literally from “Claim 1,” instead of the one having “largest protective scope.” In light of this, the applicant may try to place the “small” independent claim as Claim 1 and then re-arrange other independent claims in an ascending order. In this way, the examiner will be compelled to search against all independent claims from the first to the last.

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