Delhi High Court Cancels 'DAPLOGIN' Trademark Registration Over Similarity With Dr. Reddy's 'DAPLO'

The Delhi High Court on 17 August cancelled Razenta Pharmaceuticals' trademark registration for “DAPLOGIN” in a dispute with Dr. Reddy's Laboratories over the latter's registered “DAPLO” mark.

Justice Jyoti Singh allowed Dr. Reddy's Laboratories' petition under Section 57 of the Trade Marks Act, 1999, and directed the Registrar of Trade Marks to rectify the register by cancelling Razenta Pharmaceuticals' registration within six weeks. She held:

“The mark DAPLO is neither publici juris nor common or generic. It is a coined and distinctive mark, conceived by the Petitioner by combining 'DAP' and 'LO'.”

Dr. Reddy's Laboratories approached the Court seeking cancellation of Razenta Pharmaceuticals' registration for “DAPLOGIN” in Class 5. It claimed to be the prior adopter and registered proprietor of “DAPLO” since 2020 and described the mark as a coined word having no dictionary meaning. Both marks are used for medicines to treat Type 2 Diabetes Mellitus.

“DAPLOGIN” was published in the Trade Marks Journal on 17 June 2024. Dr. Reddy's Laboratories said the publication escaped its notice and that it did not oppose the mark at that stage. The mark subsequently proceeded to registration on 1 November 2024. Dr. Reddy's Laboratories said it discovered the registration only in March 2025 after finding “DAPLOGIN” listed on the Tata 1mg website.

The Court found that “DAPLO” was neither generic nor common to the trade and held that Razenta Pharmaceuticals' mark was phonetically similar to it. It held:

“If the two marks are compared as a whole, there is a phonetic similarity since the word DAPLO with two syllables will be pronounced as 'DAP-LO' and the word DAPLOGIN will be pronounced as a three syllable word i.e., 'DAP-LO-GIN', which means that while pronouncing DAPLOGIN, the word DAPLO will be prominently pronounced.”

The Bench also questioned the adoption of “DAPLOGIN”, noting that Razenta Pharmaceuticals had adopted the mark with “DAPLO” as its prefix and dominant part despite Dr. Reddy's Laboratories already using the mark for a drug used to treat diabetes. It observed:

“One wonders why Respondent No.1 adopted DAPLOGIN with DAPLO as a prefix and a dominant part of its mark, knowing that DAPLO was Petitioner's mark and that too for a drug used for treatment of Diabetes.”

Razenta Pharmaceuticals relied on the defence that “DAPLO” was common to the trade. However, the Court noted that it had cited only four other marks containing the “DAPLO” prefix and had produced no evidence showing that those marks were actually being used in the market. It also applied the heightened scrutiny required in cases involving pharmaceutical trademarks, relying on the Supreme Court's decision in Cadila Health Care Ltd. v. Cadila Pharmaceuticals Ltd.

It reiterated that confusion between medicinal products “may be life threatening, not merely inconvenient” and that the fact that both medicines are sold on prescription does not eliminate the possibility of confusion. Consequently it held that “DAPLOGIN” violated Sections 9(1)(a), 9(2)(a) and 11(1)(b) of the Trade Marks Act, 1999.

Accordingly, the High Court allowed the petition, cancelled Razenta Pharmaceuticals' registration for “DAPLOGIN” and directed the Registrar of Trade Marks to rectify the register within six weeks.