Timing and Eligibility for Filing Patent Infringement Suits

You’ve spent years developing an invention, filed your patent application, and finally received the grant. Then one day, you discover someone is manufacturing and selling your patented product without your permission. Your first instinct is to rush to court – but can you? And how quickly must you act? Under Indian patent law, the answers depend on two critical factors: when you can file the suit and who is legally entitled to file it. Getting either of these wrong can cost you the case before it even begins.

The starting point: when can infringement proceedings begin? 🔗

A common misconception is that you can sue for patent infringement the moment you file your patent application. That is not how it works. Under the Patents Act, 1970, the right to institute infringement proceedings does not arise until the patent is formally granted. Filing an application gives you priority in claiming the invention, but it does not give you enforceable rights against third parties.

That said, the law does offer some protection for the period between the publication of your application and the actual grant. Once a patent application is published (which typically happens 18 months from the date of filing), the details of the invention become publicly accessible. If someone begins infringing your invention during this pre-grant window, you cannot sue them immediately – but you are not entirely without recourse. After the patent is granted, you can claim damages retrospectively from the date of publication of the application, covering the period during which the invention was publicly disclosed but the patent was not yet granted.

This means the publication date serves as the earliest anchor point for calculating damages, even though the suit itself can only be filed after the grant. It is a practical protection that prevents infringers from exploiting the often-lengthy period between publication and grant with impunity.

The three-year limitation period 🔗

Once a patent is granted and infringement occurs, the clock starts ticking. As specified under the Limitation Act, 1963, a suit for patent infringement must be filed within three years from the date of infringement. Miss this window, and you may permanently lose the right to seek legal remedies for that act of infringement.

A few important nuances apply here:

Continuing infringement: If infringement is not a one-time act but an ongoing activity – for instance, a competitor continuously manufacturing your patented product – the three-year period is calculated from the date of the last infringing act. This means the limitation period effectively resets with each new act of infringement, giving the patent holder a rolling window to take action.

Lapsed patents: If a patent ceases to have effect due to non-payment of renewal fees, the patentee cannot institute proceedings for infringement that occurred during the lapsed period – specifically, between the date the patent lapsed and the date the application for restoration was published. This is a significant point: maintaining your patent by paying renewal fees on time is not just administrative housekeeping; it directly affects your ability to enforce your rights.

Who can file a patent infringement suit? 🔗

Not everyone with an interest in a patent can walk into court and file a suit. Indian law precisely defines who holds the right to initiate infringement proceedings. The registered owner of the patent, or the assignee thereof, is entitled to sue for infringement. Beyond these two primary parties, the law extends the right to a few others under specific conditions.

1. The patentee 🔗

The most straightforward case. The patentee – the person or entity to whom the patent is granted – has the primary right to file a suit for infringement. Under Section 48 of the Patents Act, 1970, the patentee holds exclusive rights to prevent any third party from making, using, offering for sale, selling, or importing the patented invention without consent. Any violation of these rights gives the patentee a cause of action.

2. Joint owners 🔗

A patent can be jointly owned by two or more persons. In such cases, each co-owner has rights in the patent, but the rules on who can file a suit may depend on the terms of their agreement. Generally, a co-owner can bring an action for infringement, but the conduct of the proceedings and distribution of remedies between joint owners can be subject to separate arrangements.

3. Exclusive licensees 🔗

Section 109(1) of the Patents Act, 1970 grants exclusive licensees the same right as the patentee to institute a suit, but only for infringement committed after the date of the licence. An exclusive licence, by definition, excludes even the patentee from exercising certain rights – making the exclusive licensee effectively the primary commercial exploiter of the patent. It follows logically that such a licensee should be able to protect those rights in court.

There is, however, a procedural requirement: when an exclusive licensee files a suit, the patentee must be added as a party – either as a co-plaintiff, or if the patentee refuses to join voluntarily, as a defendant. The patentee added as a defendant in such circumstances is not liable for costs unless they choose to appear and participate in the proceedings.

4. Compulsory licensees 🔗

A compulsory licence is one granted by the government under Section 84 of the Patents Act, typically when a patentee fails to make the invention available to the public at a reasonable price or does not work the patent in India sufficiently. Under Section 110 of the Act, a compulsory licensee does not have an immediate right to sue. Instead, they must first notify the patentee of the infringement and call upon the patentee to initiate proceedings. If the patentee fails or refuses to do so within two months of such notice, the compulsory licensee can then institute proceedings in their own name, as if they were the patentee – and the patentee is made a defendant in the process.

5. Assignees 🔗

An assignee is a person or entity to whom the patentee has transferred the patent rights. Assignees have the right to sue for infringement, but there is a critical condition: the assignment must be registered in the Register of Patents maintained by the Patent Office. An unregistered assignment agreement is not accepted as proof of ownership for the purpose of instituting proceedings. This is a statutory requirement under Section 69 of the Act, and it underscores how vital formal registration is – not just for clarity of title, but for enforceability of rights in court.

Why registration and documentation matter so much 🔗

A recurring theme across all eligible parties – exclusive licensees, assignees, and compulsory licensees – is that their right to sue hinges on proper documentation and registration. An exclusive licensee whose licence agreement is not registered with the Patent Office, or an assignee whose assignment deed has not been recorded, may face serious procedural challenges when they attempt to file a suit.

Section 69 of the Patents Act requires that any assignee or licensee of a patent make an application to the Controller for registration of their title in the Register of Patents, along with the underlying agreement. Failure to comply means the court may not recognise their standing to sue. This is not a technicality that courts overlook – it is a substantive requirement that directly determines whether a party has locus standi (the legal right to bring a case).

For students and practitioners, this means advising clients to register licence agreements and assignments without delay, and not to treat this step as optional paperwork to be addressed later.

Where to file the suit 🔗

Once you have confirmed the timing and your eligibility, the next question is jurisdiction. A patent holder can file a suit for infringement in the District Court or High Court, depending on the pecuniary value of the claim and the nature of the dispute. The High Courts of Delhi, Bombay, Calcutta, Madras, and Himachal Pradesh exercise original jurisdiction for patent infringement matters subject to their respective pecuniary thresholds.

Territorially, the suit can be filed where the plaintiff resides, carries on business, or where the infringing act took place. If the defendant counters by filing for revocation of the patent, the suit is automatically transferred to the High Court, since only a High Court can adjudicate on the validity of a patent in such circumstances.

Patent infringement suits are treated as commercial disputes and are heard under the framework of the Commercial Courts Act, 2015, which aims to ensure faster resolution of high-value commercial disputes.

A quick recap of the key rules 🔗

To put it plainly: no infringement suit can be filed before the patent is granted. Damages, however, can be claimed from the date the application was published. The suit must be filed within three years of the infringing act, with the clock resetting for each continuing act of infringement. And the right to sue belongs to the patentee, assignees with registered title, exclusive licensees (with the patentee impleaded), and compulsory licensees who have given the patentee a two-month notice opportunity. In every case, registration and documentation of rights are not formalities – they are prerequisites.

What do you think? If an exclusive licensee discovers infringement but the patentee refuses to be joined as a party in the suit, should the law provide a stronger mechanism to protect the licensee’s rights independently? And given that unregistered assignments cannot be used to establish standing in court, does the current registration requirement strike the right balance between formality and practical enforceability?

References

1. https://www.indiacode.nic.in/bitstream/123456789/1392/1/A1970-39.pdf
2. https://blog.ipleaders.in/concept-patent-infringement/
3. https://brainiac.co.in/patent-infringement-suit-in-india/
4. https://www.wipo.int/patent-judicial-guide/en/full-guide/india/6.6
5. https://ssrana.in/ip-laws/patents/patent-infringement-india/
6. https://www.caclubindia.com/acts/31021-section-109-patents-act-1970.asp
7. https://www.legal500.com/guides/chapter/india-patent-litigation/
8. http://www.nishithdesai.com/Content/document/pdf/ResearchPapers/Patent_Litigation_in_India.pdf
9. https://thelawcodes.com/article/suits-concerning-infringement-of-patents/