Summary
In the case of M/s Hi Tech Chemicals Limited vs Deputy Controller of Patents and Designs & Anr., the Madras High Court held that additional evidence in post-grant opposition proceedings must conform strictly to Rules 57 to 60 of the Patents Rules. It ruled that documents filed after the hearing is fixed without prior leave or proper notice cannot be considered, and distinguished between "publications" and private documents.
Admissibility of Evidence in Patent Opposition
Hi Tech Chemicals Limited filed a post-grant opposition under Section 25(2) of the Patents Act against a patent granted to Allied Metallurgical Products. The opposition was rejected by the Controller. Hi Tech Chemicals appealed, challenging among other things the exclusion of documents it filed as “further evidence A” and “further evidence B” after the hearing date had been fixed.
Questions Before the Court
- Can additional evidence be filed after the hearing has been fixed under Rule 62 of the Patents Rules?
- Does the term “publication” in Rule 62(4) include private documents like invoices and test certificates?
Arguments Presented By the Parties
Appellant (Hi Tech Chemicals Limited):
- Argued that the additional documents filed, including invoices and court pleadings, qualified as “publications” under Rule 62(4).
- Claimed that the documents were relevant to novelty and inventive step challenges under Sections 25(2)(d) and (e).
- Relied on Section 74 of the Evidence Act and foreign decisions to argue that some of the documents should be treated as public.
Respondent (Allied Metallurgical Products Pvt Ltd):
- Stated that Rules 55 to 62 of the Patents Rules prohibit the filing of additional evidence after the hearing is fixed, unless permitted under Rule 60.
- Said that the documents in question were private and did not qualify as “publications.”
- Argued that no leave was sought before filing the additional documents.
Court on Admissibility of Evidence in Post-Grant Opposition
The court stated that Rules 57 to 59 prescribe the stages for submitting evidence. Rule 60 permits further evidence only with leave of the Controller, and such leave must be sought before the hearing is fixed. Once the Controller sets the hearing date under Rule 62, further evidence cannot be introduced without prior approval.
The court interpreted Rule 62(4), which allows reliance on “publications” at the hearing if five days’ notice is given. It stated that the term “publication” should be limited to documents made available to the public.
Private documents such as invoices, consignment notes, and test certificates do not qualify under this rule.
The court further stated that accepting such documents after the hearing was fixed would go against the framework laid out in the Patents Rules.
Findings
The court upheld the Controller’s rejection of additional documents filed after the hearing was fixed. It stated that the documents were filed in violation of the Patents Rules and did not qualify as publications under Rule 62(4). The appeal was partly allowed for other reasons, but not on the issue of admissibility of additional evidence.
Relevant Paras
Para 27: “Such further evidence was rejected on the ground that it had been submitted in contravention of the Patents Rules.”
Para 30: “The proviso to Rule 60 makes it clear that any request for leave or direction under Rule 60 should be made before the Controller fixes the hearing.”
Para 32: “The statutory intent not to permit parties to adduce further evidence, even with the leave of the Controller, after the hearing has been fixed, is clear from Rules 57 to 60.”
Para 33: “Invoices and consignment notes are documents issued by the seller to the buyer. A permit issued by the State Commercial Tax Department is issued to a particular person… They do not qualify as publications.”
Case Citation
M/s Hi Tech Chemicals Limited vs Deputy Controller of Patents and Designs & Anr., C.M.A.(PT) No.43 of 2023, decided on 18 November 2025, Madras High Court.
Indian Kanoon Link: http://indiankanoon.org/doc/10122295/ (Visited on 20 December 2025)
Disclaimer
This case blog is based on the author’s understanding of the judgment.
Understandings and opinions of others may differ. An AI application was used to generate parts of this case blog. Views are personal.
