1. Introduction

Invalidation defense is a powerful weapon for an accused infringer during patent litigation. If a patentee asserts that a product infringes not only the independent but also dependent claims, it generally is not easy to find the appropriate prior art against the dependent claims since they normally define specific embodiments. In addition to the issue of obviousness, defendants often question the support, definiteness and enablement of a patent. In the following example, the defendant successfully proved that certain claims of the disputed patent were invalid by relying on the opposition reasons and exhibits in corresponding patent invalidation proceedings. (2018 Min Zhuan Su Zi, No. 20 by the Intellectual Property Court, 2019 Min Zhuan Shang Zi, No. 24 by the Intellectual Property Court and 2021 Tai Zhuan Zi, No. 923 by the Supreme Court)

2. Facts

The plaintiff is the owner of TW Invention Patent No. I589448 entitled “Temperature and Corrosion Stable Surface Reflector.” The patent term is from July 1, 2017 to October 26, 2035. The plaintiff asserted that the disputed product manufactured by Company A and distributed by Company B infringed claims 1 to 3, 8 to 16 and 30. In this regard, the plaintiff filed a lawsuit claiming compensation in the amount of NTD 20 million plus interest according to Paragraph 1, Article 41 of the Patent Act, Paragraphs 1 to 3, Article 96 of the Patent Act, Paragraph 2, Article 177 of the Civil Act, Article 179 of the Civil Act, former part of Paragraph 1, Article 184 of the Civil Act, Article 185 of the Civil Act, and Article 23 of the Company Act.

3. Main Issues

The invalidation issues raised by the defendant are as follow:

(1)  Whether the following combination of prior art references can prove that claims 1 to 3, 8 to 16 and 30 do not constitute improvements:

a. The combination of the prior art references stated in the Table on pages 2 to 5 of Answer (2) submitted by defendant (Company A). Further, the scope of the term “prior art admitted by the disputed patent is specified in the Table on pages 6 to 14 of Answer (2).

b. The combination of evidence items Nos. 40 (including Nos. 40-1 to Nos. 40-5) and 41, or evidence items Nos. 40, 41 and 7 (or 9).

(2)  Whether or not the specification meets the requirements for enablement stipulated in Paragraph 1 of Article 26 of the Patent Act.

(3)  Whether or not claims 1 to 3, 8 to 16 and 30 are supported by the description of the invention and lack definiteness based on Paragraph 2 of Article 26 of the Patent Act.

4. Summary of the judgments

(1) In accordance with Paragraph 2 of Article 22 of the Patent Act, an invention that is without the circumstances prescribed in the subparagraphs of the preceding paragraph but can be easily made by a person ordinarily skilled in the art based on prior art shall not be patented.

(2) The judge in the first instance considered that evidence items Nos. 40-1 and 40-2 relate to the opposition reasons of the corresponding EP patent, and evidence items Nos. 40-3 to 40-5 are related to its opposition exhibits. Even though evidence items Nos. 40-3 to 40-5 were submitted in the form of photocopies, i.e., not original copies, the defendant had clearly stated the connection between the disputed patent and the opposition exhibits of the corresponding EP patent. Evidence items Nos. 40-3 to 40-5 relate to the layered structure of the product sold by the plaintiff prior the filing date of the disputed patent. In this regard, it is acceptable to adopt evidence items Nos. 40-3 to 40-5 as invalidation evidence. Finally, after considering the invalidation defense raised by the defendant, claims 1 to 3, 8 to 16 and 30 were deemed to lack improvements in view of the combination of evidence items Nos. 40, 41 and 7.

(3)  Although the plaintiff filed an appeal, the judgment in the second instance determined that this appeal was groundless. The appellant filed another appeal against the judgment in the third instance, but eventually the Supreme Court also dismissed this appeal. This dispute is finally settled and binding on both parties.

Reference: Anthology for the 70th Anniversary of Tai E's Law Practice