In a recent order, dated 12 June, 2012 (available over here), the Intellectual Property Appellate Board (IPAB), acting on a petition filed by Tata Chemicals, has revoked Indian Patent No. 195937 granted to Hindustan Unilever Ltd. (HUL) on the 26th of August, 2005 for the invention of a ‘filter cartridge’ that is used in HUL’s Pureit brand of water-filtration devices.
While Tata Chemicals was represented Senior Advocate P.S. Raman who was briefed by Essenese Obhan, Managing Partner of the promising young patent law firm – Obhan & Associates; HUL was represented by veteran patent litigator - S. Majumdar of Majumdar & Co.
The judgment, penned by Justice Prabha Sridevan, is very interesting and covers some new ground with respect to disclosure requirements under Section 8 of the Patents Act, 1970 and also the role of expert witnesses in Indian patent litigation.
For those of you curious about the face behind Mint’s excellent reporting on IP, please do click here to view a video of C. H. Unnikrishnan explaining the significance of the IPAB’s decision.
A. The invention – Patent No. 195937: The claimed invention is constructed in such a manner that it forces the water introduced in it to climb in an upward direction through the filter media before exiting the invention as a purified water. The claimed advantage of such a mechanism was an increased rate of flow of water through the filter cartridge when compared to traditional water filters which forced water through the filter cartridge in a downward mechanism. The reason for this increased rate of flow of water was because water moving in an upward direction does not face the problems of ‘airlocks’ and ‘channelling of water’ which are common problems faced by water moving in a downward direction through a filter media. Of course, this is an over-simplified version of the actual patent specification and although the claimed invention may seem simple, the IPAB makes it very clear that simplicity was not its main ground for revoking the patent.
B. The ‘anticipation’ & ‘obviousness’ challenge: Tata Chemicals challenged the patent as being anticipated and lacking an inventive step when compared to prior art. The IPAB examines the prior art in considerable detail and appears to have found several prior art documents anticipating and rendering obvious the present invention.
In one such instance the IPAB states “It is not the simplicity of the invention that makes us hold it is not patentable It is not patentable because it is not new as seen from US ‘260, and it is obvious as seen from US ‘402 which provides for “the vertical upward flow through the absorbent cartridge” which was also addressed to remove the tendency of water to flow in channels leaving portion of absorbent untouched because air remains in the cartridge. The problems of air bubbles, channelling and non-uniform flow are all mentioned here. We are unable to see either novelty or inventive step in the invention.”
C. Section 8 challenge: Section 8 of the Patents Act, 1970 requires Indian patent applicants to disclose all details of corresponding foreign patent applications. While the Section 8 argument has been used previously in context of patent prosecution in foreign countries, the issue that cropped up in this present case was whether Section 8 could be extended to patent prosecutions before international non-governmental organizations under international treaties – the context in the present case being the International Preliminary Examination Report (IPER) issued by WIPO under the PCT.
The HUL patent application had been issued an extremely adverse IPER by WIPO and the same had not been disclosed before the Indian Patent Office. The most significant piece of prior art cited in the IPER, was reportedly an EP-1106578. Coincidentally this same EP patent was also cited by the Indian Patent Office during its examination and HUL managed to overcome the objections. HUL therefore argued that the non-disclosure of the IPER was inconsequential, since the prior art cited in the report, was duly considered by the Indian Patent Office. The IPAB however considered the suppression vital enough to constitute a separate ground for revocation of the patent. In pertinent part the IPAB states, after a detailed discussion into Section 8,
“106. The respondent cannot be heard to say that since European Patent No.1106578, the prior art was anyway considered by the Controller and no prejudice was caused by not disclosing the ISR or IPER. It is not enough that the Examiner knew that this prior art was there, the respondent ought to have disclosed the results of the IPER. The IPER rejected the claims 1 to 3 on both the grounds of novelty and inventive step. It is not for us to conjecture what effect this might have had on the examiner here if he had the benefit of the IPER. This is the object and purpose of enacting Section 8. The Report says that this information would be of great use for a proper examination of the application. It is no answer to say anyway the office looked at EP’578. The Patent Office did not see the IPER. The learned counsel for the respondent submitted that this lapse is of a de-minimis nature, we do not think that honestly furnishing the information or particulars allows a de-minimis qualification.”
Moral of the story: Start filing your IPERs and ISRs with the Indian Patent Office.
D. The role of expert witnesses: This judgment is probably one of the first to discuss the roles of expert witnesses in a patent revocation petition. Some of the important observations are as follows:
(i) “An expert is a witness of fact and his evidence is in the nature of an advice. It is not his opinion but the reasoning with which he supports his opinion, that is the principal contribution of the expert”;
(ii) “We find as a rule the experts called upon by the parties before us file affidavits. These affidavits are naturally drafted by the respective advocates. So they read almost like the statement of case or counter statement depending on who has called the witness. Instead it may be better to just get their opinion in the form of an affidavit. This opinion will deal with the prior art, the common general knowledge, this invention and why the expert is of the opinion that it is anticipated or not, it is obvious or not. Even when the affidavit has to counter the opinion of the other side expert, it is better merely to say that the expert disagrees with the opinion and for what reason.”