C.A.(COMM.IPD-PAT) 17/2024 $~1 * IN THE HIGH COURT OF DELHI AT NEW DELHI + C.A.(COMM.IPD-PAT) 17/2024 EMD MILLIPORE CORPORATION .....Appellant Through: Mr. Rohit Rangi and Mr. Ankush Verma, Advocates. versus ASSISTANT CONTROLLER OF PATENTS AND DESIGNS .....Respondent Through: Ms. Anubha Bhardwaj, CGSC with Ms. Ananya Shamshery and Mr. Vijay Mishra, Advocates. CORAM: HON'BLE MS. JUSTICE JYOTI SINGH O R D E R % 17.03.2026 1. This appeal is filed on behalf of the Appellant under Section 117A(2) of the Patents Act, 1970 (‘1970 Act’) seeking quashing and setting aside of order dated 19.01.2024 passed by the Respondent refusing to grant patent in Patent Application No. 201614010107. 2. Appellant filed a patent application before the Indian Patent Office on 23.03.2016 and was allotted Patent Application No. 201614010107. Respondent examined the application and issued the First Examination Report (‘FER’) on 21.10.2019. Appellant filed reply to FER on 25.02.2020. Hearing was scheduled for 11.03.2022, whereafter Appellant filed written submissions on 23.03.2022 in support of the patentability of the invention claimed along with amended claims 1-10. Respondent issued the impugned This is a digitally signed order. The authenticity of the order can be re-verified from Delhi High Court Order Portal by scanning the QR code shown above. The Order is downloaded from the DHC Server on 24/03/2026 at 12:19:17 C.A.(COMM.IPD-PAT) 17/2024 order on 19.01.2024 refusing grant of patent on the ground that the invention claimed in claims 1-10 lacks inventive step in light of prior art documents D1, D2 and D4. 3. At the outset, learned counsel for the Appellant, without entering into the merits of the case and without prejudice to the contention that the claimed invention does not lack inventive step, submits that the Appellant has amended the claims of the subject application in line with the claims intended to be granted in the corresponding European Divisional Application, which are similar to claims of Auxiliary request filed in the present appeal and therefore, the matter be remanded back to the Respondent for fresh examination of the amended claims. It is urged that corresponding applications filed in major jurisdictions inter alia Japan, Korea, Singapore and USA have proceeded to grant of patents. 4. Learned counsel for the Respondent, on instructions, does not dispute the legal position that amendments to claims can be carried out at the appellate stage, if warranted and that Respondent has no objection if the matter is remanded for fresh consideration of the amended claims. 5. Heard. 6. Appellant is a US Corporation and filed the subject application on 23.03.2016 at the Indian Patent Office claiming priority from US Application No. 62/144,533 dated 08.04.2015. In the FER, Respondent raised an objection of lack of inventive step under Section 2(1)(j) of 1970 Act in view of prior arts D1 and D2. Application was further examined and in the hearing notice, two additional prior arts D3 and D4 were introduced. Appellant filed written submissions as also orally argued the matter explaining how the claimed invention did not lack inventive step, however, This is a digitally signed order. The authenticity of the order can be re-verified from Delhi High Court Order Portal by scanning the QR code shown above. The Order is downloaded from the DHC Server on 24/03/2026 at 12:19:17 C.A.(COMM.IPD-PAT) 17/2024 the impugned order was passed refusing to grant the patent. 7. The claimed invention relates to a method of integrity testing, a so- called “liquid sterilizing grade filter”, which is a filter capable of retaining a B.diminuta at a level of 1x107 cfu/cm2, at a differential pressure of 206.8 kPa (30 psi). The filters are also referred to as “0.22 μm-rated filters”. The liquid sterilizing grade filters are used in sterilization of aseptically produced liquid pharmaceutical and biopharmaceutical products and use of those of filters in the production of liquid pharmaceutical and biopharmaceutical products are regulated by various authorities. 8. Along with the present appeal, Appellant has filed an Auxiliary Request and the amended claim is as follows:- “1. A method of integrity testing a filter in the dry state, comprising: providing a liquid sterilizing grade filter to be tested in a dry state, wherein said liquid sterilizing grade filter is a filter capable of totally retaining a B. diminuta challenge level of 107 cfu/cm2 at a differential pressure of 30 psi and wherein said filter is a 0.22 μm-rated filter; generating an aerosol particle stream to challenge the said filter, wherein- , the concentration of aerosol particles in the stream is in the range 105 to 107 particles/cm3, and aerosol particle sizes is in the range 10-1000 nm in diameter and the aerosol particle stream is generated at a pressure of at least 5 psig the particles in said stream have a suitable size and a suitable concentration to challenge said filter and penetrate any defective region in said filter but will not penetrate integral regions in said filter; and detecting particles that penetrate said any defective region of the said filter. 2. The method as claimed in claim 1, wherein particles that penetrate defects in said filter that are as small as 2 microns are detected by said step of detecting particles that penetrate said defective region. 3. The method as claimed in claim 1, wherein said filter is pleated. 4. The method as claimed in claim 1, wherein said filter is housed in a cartridge. 5. The method as claimed in claim 1, wherein said aerosol particle stream comprises NaCl. This is a digitally signed order. The authenticity of the order can be re-verified from Delhi High Court Order Portal by scanning the QR code shown above. The Order is downloaded from the DHC Server on 24/03/2026 at 12:19:17 C.A.(COMM.IPD-PAT) 17/2024 6. The method as claimed in claim 1, wherein said filter is a PVDF filter. 7. The method as claimed in claim 1, wherein said filter is a PES filter. 8. The method as claimed in claim 1, wherein said particles in said aerosol particle stream have a size and concentration to penetrate a defect less than 20 μm in diameter in said filter. 9. The method as claimed in claim 1, wherein the aerosol particle stream is generated at a pressure of 5-60 psig. 10. The method as claimed in claim 1, wherein said aerosol particle stream is generated by a plurality of atomizers.” 9. Section 59 of 1970 Act deals with amendment of patent applications and provides that: (a) an amendment to a patent application, including the complete specification, can be made only be way of ‘disclaimer’, ‘correction’ or ‘explanation’; (b) amendment has to be for the purpose of incorporation of actual facts; and (c) amendment cannot be in respect of matters not disclosed in the specification prior to the amendment and the amended claims have to fall within the scope of claims as originally filed. On examination of the Auxiliary Request, I am of the view that the amendment sought does not broaden the scope of unamended claim in any manner and its subject matter is disclosed in the specification and this is not disputed by the Respondent. 10. Accordingly, the proposed amendment is allowed and amended claim is taken on record. Appellant shall file the complete amended specification, including amended claim before the Patent Office and as and when the requisite steps are taken, Respondent shall proceed to examine the matter taking into consideration the amended claim. 11. This appeal is partially allowed setting aside the impugned order dated 19.01.2024 and remanding the matter back to the Respondent for taking a fresh decision after giving a fresh hearing notice to the Appellant This is a digitally signed order. The authenticity of the order can be re-verified from Delhi High Court Order Portal by scanning the QR code shown above. The Order is downloaded from the DHC Server on 24/03/2026 at 12:19:17 C.A.(COMM.IPD-PAT) 17/2024 followed by opportunity of hearing. Every endeavour shall be made to decide the application as expeditiously as possible and not later than six months from today. 12. The appeal stands disposed of, making it clear that this Court has not expressed any opinion on the merits of the case. JYOTI SINGH, J MARCH 17, 2026/YA This is a digitally signed order. The authenticity of the order can be re-verified from Delhi High Court Order Portal by scanning the QR code shown above. The Order is downloaded from the DHC Server on 24/03/2026 at 12:19:17