Under Section 7(2) of Indian Patents Act, “proof of right” means showing how the person who has filed the patent application legally obtained the right to do so, when that person is not the true and first inventor. Indian patent law proceeds on the foundational principle that the right to a patent first belongs to the true and first inventor, because the invention originates from that person’s intellectual effort. However, in practice, patent applications are often filed by companies, employers, or assignees, rather than by the inventor themselves. In such cases, the Patent Office must be satisfied, through documentary evidence, that the right to apply for the patent has been validly transferred from the inventor to the applicant. This evidence is what the Act calls “proof of right”. It is usually shown through an assignment deed, an employment agreement containing an invention assignment clause, or any other legal document that transfers the right to apply for a patent from the inventor to the applicant. Without this proof, the Patent Office cannot be satisfied that the applicant is entitled to seek the patent.

This provision was recently examined in detail by the Delhi High Court in Nippon Steel Corporation vs Controller of Patents [C.A.(COMM.IPD-PAT) 10/2025], in the context of a refusal based solely on the ground of lack of proof of right.

The subject patent application, number 202117029591, entitled “High-Strength Steel Sheet and Manufacturing Method of High-Strength Steel Sheet”, was filed by Nippon Steel Corporation as an assignee in respect of an invention developed by four inventors, all of whom were its employees. One of the inventors, Mr. Kohichi Sano, had passed away prior to the conclusion of prosecution. At the time of filing, Nippon Steel submitted Form 1 executed by the remaining inventors (it did not contain the signature of the deceased inventor), along with a declaration enclosing the company’s internal “Basic Regulations” governing intellectual property, which stipulated that inventions made by employees in the course of employment vested in the company. During prosecution, and in response to objections raised in the First Examination Report, Nippon Steel also placed on record the employer-employee agreement executed with Mr. Kohichi Sano to demonstrate that the right to apply for the patent had already vested in Nippon Steel during the inventor’s lifetime.

Despite these documents being on record, the Controller refused the application on the ground that the applicant failed to satisfy the requirements under Sections 6(1)(b), 6(1)(c) and 7(2) of the Act. The Controller took the view that an employment agreement, by its general nature, could not constitute valid proof of right under Section 7(2) of the Act. According to the Controller, in the absence of a specific assignment deed or an assignment executed by the legal representative of the deceased inventor under Section 6(1)(c), Nippon Steel could not be treated as an assignee. The Controller further relied on Section 68 of the Act to hold that assignment must be in writing and duly executed, and concluded that the applicant had failed to satisfy the requirements under Sections 6(1)(b), 6(1)(c) and 7(2), warranting refusal under Section 15.

On appeal, the Delhi High Court first carefully situated the dispute within the statutory framework governing entitlement to apply for a patent. The Court noted that Section 6 of the Act expressly recognises the right of an assignee of the true and first inventor to file a patent application, and that Section 7(2) requires such an assignee to furnish proof of the right to make the application within the prescribed period. Importantly, the Court clarified that Section 6(1)(b) does not restrict the nature of documents through which such proof may be established, nor does it exclude employment agreements from the scope of acceptable evidence. The Court emphasised that the present case concerned assignment of the right to apply for a patent, and not assignment of a granted patent, rendering the Controller’s reliance on Section 68 misplaced.

Applying this understanding, the Court held that an employment agreement entered into between the employer (assignee) and the employee (inventor), duly executed during the course of employment and read together with binding corporate IP regulations, is capable of constituting valid proof of right under Section 7(2). Since the deceased inventor’s contractual obligations had already vested the rights in the employer during his lifetime, there was no surviving right that required a fresh assignment from the legal representative under Section 6(1)(c). The Court thus rejected the Controller’s hyper-technical approach and reaffirmed that procedural laws are intended to subserve and not to subvert the cause of justice.

In view of the foregoing, the Court allowed the appeal and directed that the subject application proceed towards grant.