In the case of Milliken and Company vs Controller of Patents and Designs & Anr. [C.A.(COMM.IPD-PAT) 15/2023], the Delhi High Court set aside the order passed by the Controller that refused patent application number 6093/DELNP/2013, entitled “Additive Compositions and Thermoplastic Polymer Compositions Comprising the Same”. The Court addressed some critical aspects of patent law, particularly the treatment of expert evidence, reliance on decisions passed in foreign jurisdictions, and the handling of post-hearing submissions.

It was the case of the Appellant that the impugned order was passed without taking into consideration the testimony of Dr. Nathan A. Mehl filed by the Appellant along with the post-hearing submissions before the Controller.

The Controller tried to justify the rejection of the testimony by contending that it was filed nearly nine years after the filing of the patent application. The Controller also argued that Dr. Mehl, being an employee of the Appellant, could not be treated as an independent expert. Additionally, it was pointed out that the European Patent Office (EPO) Board of Appeals had rejected the statement of Dr. Mehl citing the delay in its submission and the fact that he was employed by the Appellant.

The Court concurred with the submissions made on behalf of the Appellant and made the following observations:  

• Timely Filing of Post-Hearing Submissions: The Court observed that, in accordance with Rule 28(7) of the Patent Rules, 2003, an applicant is permitted to submit written submissions, along with relevant documents, within fifteen days from the date of the hearing. The Court noted that since Dr. Mehl’s testimony was filed within the prescribed period for post-hearing submissions, it could not be considered belated.
• Expert’s Employment Status Irrelevant: The Court rejected the Controller’s argument that Dr. Mehl’s status as an employee of the Appellant was a valid ground for rejecting his testimony. The Court noted that the Appellant, being engaged in the manufacturing of chemical products, would naturally have technical experts in its employment.
• Independent Consideration Irrespective of Foreign Jurisdiction Decisions: The Court reaffirmed the legal position that the grant or refusal of a patent in another jurisdiction cannot, by itself, be a basis for its grant or refusal in India. Specifically, the Court referred to the judgment in Communication Components Antenna Inc. vs Ace Technologies Corp. and Ors. [2019 SCC OnLine Del 9123], wherein the Delhi High Court noted that while foreign patent claims can be referred to for consistency, the validity of a patent in India must be assessed primarily based on the claims granted in India. In the instant case, the Court remarked that the Controller ought to have independently considered the testimony of Dr. Mehl on merits, without being influenced by the fact that it had not been accepted by the European Patent Office.

Accordingly, the Court remanded the matter to the Patent Office for de novo consideration.

The decision underscores that an expert’s employment status cannot be a ground for disregarding their testimony, decisions passed in foreign jurisdictions concerning corresponding patent applications cannot be a ground for grant or refusal of a patent application in India, and any post-hearing submission filed within the prescribed period must be considered by the Patent Office.