Delhi High Court Cancels Registration of “DAPLOGIN”, Holding it Deceptively Similar to “DAPLO

Summary

The Delhi High Court, in Dr. Reddy’s Laboratories Limited v. Razenta Pharmaceuticals Private Limited & Anr., allowed a cancellation petition filed by Dr. Reddy’s Laboratories Limited and cancelled the registration of ‘DAPLOGIN’, holding it deceptively similar to the Petitioner’s prior mark ‘DAPLO’ for pharmaceutical products.

Facts of the Case

The Petitioner had coined and adopted the trademark ‘DAPLO’, which had been continuously used since 2020 for pharmaceutical products used in the treatment of “Type-2 Diabetes Mellitus”. The mark was registered in Class 5.

The Respondent applied for registration of ‘DAPLOGIN’ under Registration No. 5208898 in Class 5 on a proposed-to-be-used basis on 14 November 2021. The mark was published in the Trade Marks Journal on 17 June 2024 and was subsequently placed on the Register on 1 November 2024.

The Respondent contended that ‘DAPLOGIN’ had been independently coined from Dapagliflozin and that ‘DAP/DAPLO’ was common to trade, relying upon various third-party registrations.

Issue before the Court

Whether the registration of ‘DAPLOGIN’ was liable to be cancelled on account of its deceptive similarity with the Petitioner’s prior registered trademark ‘DAPLO’.

Findings of the Court

The Court held that ‘DAPLO’ and ‘DAPLOGIN’ were deceptively similar. Applying the anti-dissection principle, the marks were required to be compared as a whole, from the perspective of a person of average intelligence and imperfect recollection. The Court noted that DAPLO was wholly subsumed within DAPLOGIN and that the addition of “GIN” was insufficient to distinguish the marks.

The Court also considered the principle of initial interest confusion, observing that a person familiar with DAPLO could, upon encountering DAPLOGIN for the same drug, perceive it as another variant originating from or associated with the Petitioner. The likelihood of confusion was enhanced since the rival products contained the same API, treated the same disease and shared common trade channels and consumer base.

The Court rejected the Respondent’s argument that DAPLO was publici juris merely because “DAP” was derived from Dapagliflozin. It held that DAPLO was a coined word with no dictionary meaning, formed by combining ‘DAP’ and ‘LO’, and was not the prefix, suffix, abbreviation or short name of Dapagliflozin. The fact that ‘DAP’ was derived from the API did not, by itself, render the composite mark DAPLO publici juris.

The “common to trade” defence was also rejected. The Court noted that, apart from the rival marks themselves, the Respondent had produced four other registrations incorporating DAP/DAPLO, but there was no evidence demonstrating their actual use in the market. Mere presence of marks on the Register could not establish that the mark was common to trade.

Held

The Court reiterated that pharmaceutical trademarks require exacting and stringent judicial scrutiny in view of the serious consequences that may arise from confusion between medicines. The fact that the competing medicines were prescription drugs was held insufficient to rule out the possibility of confusion.

Accordingly, the Court held that the registration of ‘DAPLOGIN’ fell foul of Sections 9(1)(a), 9(2)(a) and 11(1)(b) of the Trade Marks Act, 1999.

The registration of ‘DAPLOGIN’ under No. 5208898 was cancelled, and the Registrar of Trade Marks was directed to rectify the Register within six weeks.

Conclusion

The decision reiterates that incorporation of an earlier distinctive mark in its entirety, with a mere suffix added thereto, may constitute deceptive similarity, particularly where the competing marks are used for identical pharmaceutical products containing the same API and treating the same ailment.

Last Updated on 21 September, 2026