The Petitioner, Embio Limited (Embio), sought the revocation of a patent granted to the first respondent, Malladi Drugs & Pharmaceuticals Ltd. The patent in question (Case no. (ORA/35/2014/PT/CHN); Embio Limited Vs. Malladi Drugs & Pharmaceuticals Ltd. and Ors.) pertains to a method for the preparation of new optically pure 1-phenyl-2 (N-alkyl/arylamino) propanol hydrochlorides with 100% optical purity. The petitioner raised objections regarding the novelty and inventive step of the patent, arguing that the invention was not inventive to a person skilled in the art and that it was merely a workshop improvement without technical advancement.

Embio/Petitioner argued the following in support of their case.

1. Novelty and Inventive Step: The petitioner argued that the patent lacked novelty and an inventive step. They claimed that the invention was not obvious to a person skilled in the art and that it was merely a workshop improvement without technical advancement.
2. Person Interested: The petitioner asserted that they were a ‘person interested’ since both the petitioner and the first respondent were in the same industry, dealing with similar kinds of medicines.
3. Prior Arts: The petitioner contended that the first respondent’s method was not different from prior arts. They cited several prior patents, including European Patent No. EP 1 142 864 A1 and US Patent Nos. US2,509,309 & US2004/0249212 A1, to argue that the process, steps, reactants, temperature range, catalyst used, and pressure employed were all found in prior arts.
4. Technical Advancement: The petitioner argued that the first respondent had not been able to produce any data to show technical advancement. They claimed that the process did not involve any technical advancement or economic significance and merely followed the prior arts.
5. Efficacy and Description: The petitioner further contended that the first respondent had not shown any significant improvement relating to the efficacy of the product or a new product arising from the process. They also argued that the first respondent had not sufficiently described the invention, which is an important criterion for getting a patent grant.

The Respondent/Malladi Drugs & Pharmaceuticals Ltd. (Malladi), made several key arguments in their defence:

1. Patent Publication and Opposition: The respondent argued that their patent was published as early as 2007 and was not opposed by anyone, including the petitioner, until after the grant.
2. Person Interested: They contended that the petitioner was not a ‘person interested’ as they had not produced any material to establish their claim of manufacturing Ephidrine. The respondent emphasized that Ephedrine is not the end product in their invention and that their process is completely different from prior arts.
3. Technological Advancement: The respondent claimed that their process involved a clear technological advancement, producing new Active Pharmaceutical Ingredients (API) intermediates.
4. Inventive Step: They argued that they had shown an inventive step by adopting a process for compounds different from ephedrine and its salts.
5. Range in Organic Chemistry: The respondent stated that in organic chemistry, no specific range can be given due to the long periods of time involved, and the range depends on various other factors.
6. Novelty and Technical Advancement: The respondent contended that their process for synthesizing stereo selective isomer was novel and inventive, achieving high optical purity and better yield compared to prior arts. They argued that the petitioner’s claims were based on irrelevant and immaterial prior arts.
7. Patent Examination and Amendments: The respondent highlighted that their claims were amended twice and the patent was granted only after a thorough examination by the Patent Controller, who raised various objections that were overcome by the respondent.
8. Post-Grant Challenge: The respondent argued that the petitioner’s challenge was not worthy enough to revoke the patent, as the petitioner had not established strong grounds for revocation by citing relevant prior arts and showing how the subject patent was not novel or lacked an inventive step.

Court Ruling

The court dismissed the petition for revocation of the patent, finding no merit in the petitioner’s (Embio) claims. The patent granted to the first respondent/Malladi was upheld, and the petition was dismissed without any order as to cost. The important observations are mentioned as below:

1. Person Interested: The court first examined whether the petitioner was an “interested person” competent to challenge the patent grant. The court concluded that the petitioner, being a manufacturer of Ephedrine and Pseudoephedrine salts, was indeed an interested person. The court referenced the definition under Section 2(t) of the Patents Act, 1970, which includes anyone engaged in or promoting research in the same field as the invention.
2. Novelty and Inventive Step: The court then addressed the petitioner’s objections regarding the lack of novelty and inventive step in the respondent’s patent. The court found that the respondent’s process achieved a higher yield and optical purity compared to the prior arts cited by the petitioner. The court noted that the respondent’s process was different and better than the teachings of the prior arts.
3. Technical Advancement: The court recognized that the respondent had shown technical advancement over the prior arts. The respondent’s process involved a new synthetic route and a new process for synthesizing optically pure hydrochlorides, achieving high optical purity and better yield.
4. Patent Examination and Amendments: The court highlighted that the respondent’s claims were amended twice and the patent was granted only after a thorough examination by the Patent Controller. The court found no illegality or perversity in the grant of the patent9.
5. Post-Grant Challenge: The court emphasized that the burden of proof was on the petitioner to establish strong grounds for revocation by citing relevant prior arts and showing how the subject patent was not novel or lacked an inventive step. The court found that the petitioner had not been able to discharge this burden1011.
6. Timeliness of Objection: The court also noted that the respondent’s patent was published in 2007, and no objection was raised for several years. The court found merit in the respondent’s argument that the petitioner’s challenge was not timely.

Our Comment

The threshold for filing a revocation petition is for the Petitioner to satisfy that he is a “person interested.” According to Section 64 of the Patents Act, 1970, the validity of a patent can be challenged or sought to be revoked by any person interested on the grounds mentioned in sub-sections 1(a) to 1(q). The term “person interested” is defined under Section 2(t) of the Patents Act, 1970, to include a person engaged in or promoting research in the same field as that to which the invention relates. This definition is inclusive and not static, meaning that even if a person was not initially interested, they could become so due to their activities at a later point in time. The court emphasized that the term “person interested” is not limited to manufacturers but includes anyone engaged in or promoting research in the same field.

Further, in a muti step chemical process, factor like lesser reaction time, drastically higher yield and superior purity are helpful to establish inventive step.