Patents of Addition, Grant, Term and Transfer of Patent Rights

1. Patents of addition (ss.54–56)

An inventor who has patented an invention often improves it. Without a special rule the improvement would face the main patent as prior art and might fail for want of inventive step, and a separate patent would require separate renewal fees. Sections 54 to 56 solve both problems.

• Who may apply. Only the applicant for or the patentee of the main invention may apply for a patent of addition for an improvement in or modification of that invention (s.54(1)). The Controller may also, on request, revoke an independent patent for an improvement and grant it as a patent of addition, if the patentee of both is the same (s.54(2)).
• Timing. A patent of addition is not granted before the main patent (s.54(3)).
• Term and fees. It lasts only as long as the main patent and ends with it (s.55(1)); no renewal fees are payable for it while the main patent is in force (s.55(2)).
• Revocation of the main patent. If the main patent is revoked, the Controller or court may order that the patent of addition become an independent patent for the remainder of the term, and fees then become payable (s.55(1) proviso).
• Validity. A patent of addition cannot be refused or revoked only on the ground that the invention claimed does not involve an inventive step having regard to the main invention or an earlier patent of addition (s.56(1)). It must still be new and inventive over other prior art.

Comparison. The UK had patents of addition under the Patents Act, 1949 but abolished them in 1977, relying instead on the priority system and later filings. The US uses “continuation-in-part” applications. India kept the 1949 model.

2. Grant (formerly sealing) of the patent (s.43)

As enacted in 1970, section 43 provided for the sealing of the patent: once the application was accepted and any opposition decided, the patent was sealed with the seal of the patent office on request. The 2002 and 2005 amendments, which moved opposition to the stage before grant and abolished the separate step of acceptance, recast section 43 as grant of patents. Where an application has been found in order for grant and has not been refused, and either no pre-grant opposition was made or any opposition has been decided in the applicant's favour, the Controller shall grant the patent as expeditiously as possible with the seal of the patent office, and the date of grant is entered in the register (s.43(1)). The grant is then published (s.43(2)). “Sealing” survives in older judgments and in the date of sealing used under the 1970 regime to measure the old food and drug patent terms.

Rights before grant. From the date of publication of the application (s.11A(7)) the applicant has the like privileges and rights as if a patent had been granted, but cannot sue for infringement until the patent is granted. Damages for that interval are recoverable once the patent issues. For mailbox applications, rights ran only from grant, and the patentee could claim only a reasonable royalty from enterprises that had made significant investment before 1 January 2005.

3. Date and term (ss.45 and 53)

• Date of the patent (s.45): the date on which the application was filed. For a PCT national phase application, it is the international filing date.
• Term (s.53(1)): twenty years from the date of filing, implementing TRIPS Article 33. Before 2002 the term was fourteen years, and for food, drug and chemical process patents five years from sealing or seven years from filing, whichever was shorter.
• Renewal fees (s.53(2), with the Rules): payable annually from the third year, with a grace period of six months on payment of an additional fee. If not paid, the patent ceases.
• Restoration (ss.60–62): an application to restore a lapsed patent may be made within eighteen months of lapse, showing that the failure to pay was unintentional and there was no undue delay. On restoration, persons who began to use the invention in the interval in good faith are protected (s.62).
• End of the term. On expiry the invention falls into the public domain. India has no patent term extension for regulatory delay, unlike the US (35 U.S.C. §156) and the EU's supplementary protection certificates.

4. Transfer of patent rights (ss.68–70)

A patent is personal property and can be dealt with like other property. The forms of transfer:

1. Assignment: transfer of the whole or part of the patent (for a territory, or a share), legal and equitable.
2. Mortgage: the patent as security for a loan, which is assignment of the interest subject to redemption.
3. Licence: permission to work the invention without transfer of ownership. A licence may be exclusive (s.2(1)(i) defines the exclusive licensee, who can sue under s.109), sole, or non-exclusive; voluntary or compulsory.
4. Transmission: transfer by operation of law, on death, insolvency, or amalgamation of companies.

Formalities. An assignment, mortgage, licence or creation of any other interest in a patent is not valid unless it is in writing, the agreement is reduced to a document embodying all its terms, and an application for its registration is filed with the Controller within six months of execution or within such further period as the Controller allows (s.68). A person who becomes entitled by assignment, transmission or operation of law applies to have his title registered (s.69(1)). A document not registered is not admitted in evidence as proof of title unless the court directs otherwise for reasons recorded (s.69(5)). The registered grantee or proprietor has power to assign, grant licences and deal with the patent, subject to rights recorded in the register (s.70).

Co-owners (s.50). Where a patent is granted to two or more persons, each is entitled to an equal undivided share and may make, use and sell the invention for his own benefit without accounting to the others, but none may grant a licence or assign a share without the consent of the others.

Limits on contracts. Conditions in a licence or assignment that require the licensee to buy unpatented articles from the patentee, prohibit him from using another's technology, or prevent him from challenging validity, and coercive package licensing, are void (s.140). Contracts relating to a patent may be terminated by either party on three months' notice once the patent has ceased (s.141). These limits implement TRIPS Article 40 and overlap with section 3(5) of the Competition Act, 2002.

5. Comparative note

• UK (Patents Act 1977, ss.30–33): assignment must be in writing and signed; registration is not a condition of validity but protects against later purchasers without notice and affects costs and damages in infringement actions.
• US (35 U.S.C. §261): patents have the attributes of personal property; assignments must be in writing and are void against a later purchaser for value without notice unless recorded within three months.
• EU: the European patent is a bundle of national patents for transfer purposes, but the Unitary Patent (from 2023) can be transferred only as a whole for all participating states.

How this is examined

Short notes on “patents of addition”, “sealing of patents”, “term of a patent” or “assignment and licensing of patents”. For each, give the sections, the conditions in list form and one comparative line. A 16-mark question on rights of the patentee should combine section 4 here with the note on rights and obligations.