The Calcutta High Court has overturned the Indian Patent Office’s (IPO) refusal of a divisional patent application filed by Pharmacyclics LLC, a U.S.-based biopharmaceutical company. The ruling reaffirms that divisional applications in India can be valid even if their claims differ from the parent application, as long as they find support in the original specification.
Court Restores Fair Examination
The case involved Pharmacyclics’ divisional application concerning a Bruton’s tyrosine kinase (BTK) inhibitor, used in combination therapies for cancer treatment. The IPO had earlier rejected the application, saying the divisional claims were not disclosed in the parent application’s claims and that the shift from method to product claims made it invalid.
However, the Calcutta High Court found that the IPO’s stance was inconsistent. In the first office action, the examiner had accepted the divisional as maintainable. Later, during the hearing stage, the IPO reversed its position and rejected the application on procedural grounds.
Justice observed that such a sudden change violated the principle of natural justice. Once the IPO accepted maintainability, it was obliged to proceed with substantive examination on merits instead of questioning the divisional’s validity.
Specification Support Is Key
The Court also clarified that Section 16 of the Indian Patents Act, 1970 does not restrict divisional claims to those identical to the parent application. What matters, it said, is that the divisional claims are “fairly based” on the complete specification of the parent.
Citing earlier precedents such as Syngenta Crop Protection AG v Controller of Patents and Designs, the Court reaffirmed that divisional applications can stand on their own if supported by the parent disclosure, even when their claims vary in scope or type.
Fresh Review Ordered
The Court set aside the IPO’s refusal order and directed it to re-examine the divisional application on substantive grounds, such as novelty and inventive step. It also instructed the office to ensure that applicants receive consistent and transparent treatment during prosecution.
Broader Impact on Patent Practice
This ruling strengthens the position of patent applicants in India, especially in the pharmaceutical and life-sciences sector, where divisional filings are common to protect different aspects of complex inventions.
Experts say the decision promotes procedural fairness and aligns Indian patent practice with global standards. It also encourages applicants to draft comprehensive specifications that can support multiple claim sets for future divisional filings.
While the ruling applies directly to this case, it is expected to influence other High Courts and the IPO’s approach to divisional patents in ongoing and future cases.
