How to Make Permissible Amendments to Patents

This is a period of tumultuous and exciting change for Indian intellectual property, and patent practice in particular. The Indian patent office is streamlining its service and practice guidelines; new innovators are more engaged with the IP system; patentees are actively enforcing patent rights; and generics are regularly opposing originator’s patents. Amidst these developments, one concern that frequently emerges relates to the amendments of patent applications or claims. When prosecuting a patent application or defending a revocation, patentees or applicants routinely request amendments of patent claims or descriptions. These requests intend to clarify the invention or to distinguish it from prior art. However, a lack of clarity as to the nature and extent of permissible amendments means that such requests are often refused (table 1 provides a brief summary of the amendments provided in the Patents Act 1970 (Act) and the Patent Rules 2003 (Rules). This article sheds light on the ambiguity surrounding amendments through an analysis of recent decisions on the issue.

Nature of amendments Although the Act prescribes that a patent or an application may be amended at several stages, the right to amend is conditional, and the amendment must meet the conditions provided under the Act. Section 59 elaborates these conditions. An amendement: (i) must be by way of disclaimer, correction, or explanation; (ii) must be for incorporation 2 of ac-tual fact; (iii) will not be allowed if it describes matter not in substance disclosed or shown in the unamended specification, or any claim of the amended specification does not fall wholly within the scope of a claim of the unamended specification. The three types of permissible amendments (disclaimer, explanation and correction) are further defined in terms of their essential characteristics (see table 2).

Substantial amendments to patents and applications While minor amendments are fairly straightforward to execute and obtain, the challenge arises in seeking substantial amendments relating to patent claims or descriptions. This section discusses these two types of substantial
amendments in light of recent Indian decisions.

Amendments to the claims

With international IP portfolios becoming the norm, transborder patent filings are not uncommon. In such cases, patent applicants who have had certain claims allowed in foreign applications often seek to include those additional claims in the corresponding Indian application after it has been filed, and is being prosecuted. In such cases, the additional subject matter contained in the claim, although described in the specification, would not have been included in the unamended claims. Recent decisions suggest that such inclusion of new claims would not be allowed in India. In a December 2013 decision on patent application 2584/KOLNP/2004, filed by the Glaxo Group, the Controller of Patents held that the applicant’s new claims did not fall wholly within the scope of the unamended claims, and also did not meet any of the criteria prescribed under section 59 (the new claims were not a disclaimer, correction or explanation). In AGC Flat Glass Europe v Anand Mahajan 2009, the Delhi High Court was asked to decide on a post-grant amendment bringing in a limitation from the description into the claims. The claims related to a mirror with no copper layer. The plaintiff, AGC Flat Glass Europe, wanted to insert the phrase, “a sensitizing material, typically tin” in the principal claim, on the grounds that it was an explanation to clarify the scope of the invention in light of prior art. They also said that the amendment pertained to matter already disclosed in the specifications, and did not fall outside the scope of the unamended specifications. The defendants contended that the amendment added new matter to the principal claim, and varied its scope (that is, the amendment fell beyond the scope of the claim of the original specification). The Court said that the working of the invention, as described in the specification, was based on three processes: sensitising, activating, and silvering process. The amendment, the court observed, clarified the scope of the sensitising process by specifically mentioning the sensitising material tin). This did not lead to a new invention, and objections regarding the amendment being beyond the scope of the original specifications, or being inconsistent with the original claim, were without merit. The Court held that the amendment was merely to clarify or elaborative, and at best, a disclaimer, and did not alter the scope of the invention. This suggests that a limitation from the description may be brought into the claims, so long as it does not alter the scope of the invention. In Enercon (India) v Alloys Wobben 2013, the patentee, Alloys Wobben, sought to amend the claims to avoid revocation. It requested that claim 1 relating to a “wind power installation” be amended thus: (i) the word “comprises” should be replaced with “comprising”; (ii) the term “a rotor blade” be redrafted as “each rotor blade”; (iii) the phrase “which suitably adjust…of other rotor blades” be redrafted as “the adjusting device…of the other rotor blade or the other rotor blades”; and (iv) the phrase “said rotor hub…of the hub or a rotor blade” be redrafted as “with measuring means (40)… mechanical loading of the hub”. The patentee classified these amendments as corrections. Corrections (i) and (iv) were considered allowable since they did not alter the scope of the claims, but corrections (ii) and (iii) were rejected, with the Intellectual Property Appellate Board (IPAB) pointing out that they altered the functioning of the adjusting device. Before amendment, the adjusting device was construed to adjust only one of the rotor blades to set its angle. However, after amendment, the adjusting device could be construed as adjusting each rotor blade individually to set its angle. The corrections, therefore, altered the scope of claims, and in effect widened the claims, and could not be permitted. The request for amendment of claims was hence rejected. In Diamcad and SS Borisovish v Sarin Technologies and Controller of Patents and Designs 2012, the patentees, Diamcad and SS Borisovish, appealed the refusal of the patent in a post-grant opposition before the IPAB. The patentees’ request for amending the claims had been rejected by the Controller, on grounds that 5 the revised sets of claims were not fairly supported by the description, and required the addition of new subject matter to enable a person skilled in the art to perform the invention independently. The proposed amendments changed “predetermined angle” to “arbitrary initial position”, and “obtaining two data” to “obtaining at least two data”, amongst other amendments. The IPAB rejected the amendments, observing that the amended claims would not fall wholly within the scope of unamended claims. These IPAB decisions suggest that amendments may be allowed if the amended claims are not larger than the original claims, and do not alter the scope of invention.

Amendments to the description There is often ambiguity as regards the addition of further features to a patent specification. Some argue that adding descriptive material may qualify as an explanation, and therefore allowable under law. Others suggest that such additions would amount to converting insufficient descriptions to sufficient ones. In Diamcad and SS Borisovish v Sarin Technologies and Controller of Patents and Designs, the patent was allegedly insufficiently described. To address the objections, the patentee made several amendments to the description. However, the IPAB held that as none of these elements were disclosed implicitly in the original specification, they could not be allowed. Similarly, in Spice Mobiles and Samsung India Electronics v Somasundaram Ramkumar 2012, the specification relating to a “mobile phone with a plurality of SIM cards allocated to different communication networks” was amended to insert features of the circuitry that had to be modified to accommodate two or more SIM cards and features such as headphones, earplugs, and bluetooth devices. However, these amendments were not allowed, as the IPAB said there were no explicit or implicit disclosures of these elements in the specification. These decisions clarify that the addition of any descriptive material has to be at least implicitly disclosed in the specification to be allowable, and that defective specifications may not be corrected to make them sufficient. Although the addition of further descriptive material may not be allowed, the inclusion of matter to exhibit the effects or advantages of an invention may be allowable. In Solvay Fluor v EI DuPont de Nemours 2010, the IPAB allowed the patentee’s request to include the term synergy in the description, reasoning that it would qualify as a disclaimer and a clarification. A related question arises as regards the permissibility of amendments to insert experimental results. The Manual of Patent Office Practice and Procedure offers guidance in this context: The complete specification may bring out clearly and categorically in the description, as to how the subject matter differs significantly in properties with regard to efficacy from the known substance thereof, at the time of filing of the application or subsequently by way of an amendment of specification under section 59. Thus, a request for including experimental results and implicit advantages of an invention would likely be allowable under the Act.

Understanding is key

In brief, there is no room for new added matter in claims or description that could alter the scope of invention. Claims may be amended to clarify the scope of invention, but must be in conformity with the description, and amendments may be made before or after the grant of a patent. Further, it is possible to amend a claim to overcome prior art identified during invalidation proceedings. Besides understanding how the authorities handle such requests, however, patentees and applicants would benefit from appreciating the value of additional, and perhaps more subjective, factors that could determine requests for amendments. For instance, an unreasonable delay in filing an amendment or providing incorrect reasons for seeking amendments may be regarded as misconduct on the part of the applicant, and may jeopardise an application. Further, if an applicant chooses to withhold certain prior art, but subsequently amends the application during revocation proceedings, the amendment may not be allowable. As in Enercon (India) v Alloys Wobben, courts intend to examine four principles when assessing such requests: full and fair disclosure of all relevant matter; statutory compliance; the public interest requirement of promptly seeking amendments; and, the applicant’s conduct. Careful adherence to these principles can be a sure indication of a positive outcome of requests 6 for amendments.

Table 1: Amendments permissible under the Indian Patents Act, 1970 and Patent Rules, 2003

Table 2: Types of permissible amendments