Astra Zeneca Ab And Anr. v. Natco Pharma Limited

When a patent is alive, every sale matters. A drug maker that launches a generic version while a patent is still breathing may find that even favorable later rulings cannot undo the financial safety net the original patent holder secured. This case is a stark reminder that bank guarantees are not casual paperwork; they are the price of doing business in someone else's patent territory.

AstraZeneca AB, the innovator behind the drug Dapnat (Dapagliflozin), held two Indian patents — IN 205147 and IN 235625 — covering its blockbuster diabetes medication. Natco Pharma Limited, a well-known Indian generic manufacturer, allegedly infringed these patents by manufacturing and selling its own version of Dapagliflozin. During the course of the infringement proceedings, Natco was required to furnish a bank guarantee as a condition tied to the litigation. The dispute before the court was not about the underlying infringement itself, but about Natco's attempt to get released from this bank guarantee obligation.

Natco Pharma argued that it should be freed from the bank guarantee, presumably suggesting that the obligation was no longer necessary or justified. On the other side, AstraZeneca pushed back, contending that the bank guarantee served a critical protective function. The core legal friction centered on whether the guarantee could be released when the products covered by it had been sold during the subsistence of an active patent. AstraZeneca's position was straightforward: the patents were in force when Natco sold its allegedly infringing product, and that fact alone justified keeping the financial safeguard in place.

The court sided with AstraZeneca and declined to release Natco Pharma from its bank guarantee obligation. The reasoning was clear and consequential: the continuation of a bank guarantee is necessary when products covered by it were sold during the subsistence of an active patent. Even if subsequent developments or judgments might suggest otherwise, the fact that infringing sales occurred while the patent was alive was enough to keep the guarantee intact. The outcome was firmly plaintiff-favorable, leaving Natco bound by its financial commitment.

For founders and IP professionals, the lesson is blunt: do not underestimate the long tail of patent litigation. Launching a product while a competitor's patent is active — even if you believe the patent is weak or will be invalidated — exposes your company to financial obligations that may outlive the underlying legal battle. Bank guarantees, injunctions, and similar security measures are not easily unwound. Before entering a contested market, conduct rigorous freedom-to-operate analysis, weigh the cost of litigation security, and remember that selling during the patent's lifetime creates liabilities that subsequent rulings may not erase.