In Samsung Bioepis Co, Ltd. v. Alexion Pharms., Inc., IPR2023-01070, Paper 9 (PTAB Dec. 19, 2023), the Patent Trial and Appeal Board ("the Board") instituted an inter partes review ("IPR") petition challenging all claims of U.S. Pat. No. 10,703,809 ("the '809 patent") related to Alexion's product eculizumab, marketed as Soliris®. In doing so, the Board rejected Patent Owner's 35 U.S.C. §325(d) discretionary denial arguments.


Petitioner asserted twelve grounds of obviousness based on various combinations of nine references.

Board Decision

The Board found Petitioner carried its burden to show a reasonable likelihood of showing obviousness of at least one challenged claim. In granting institution, the Board analyzed Patent Owner's §325(d) arguments and determined not to exercise its discretion to deny institution based on its analysis under the two-part Advanced Bionics framework:1

  • whether the same or substantially the same art or arguments were previously presented to the Office; and
  • if the first part of the framework is satisfied, whether petitioner has demonstrated that the Office erred in a manner material to the patentability of challenged claims.

Patent Owner explained that all nine asserted references were previously disclosed in the prosecution of the parent patent of the '809 patent.2 Thus, according to Patent Owner, because examiners consider information submitted in parent applications, all the asserted references were also considered during prosecution of the '809 patent.3 Petitioner agreed that many asserted references were cited in Information Disclosure Statements, but argued that "there is no evidence that these references were considered by the [e]xaminer."4 The Board, however, sided with Patent Owner holding that, "in view of the unique record before us," all of the references relied on by Petitioner "were previously presented to the Office" and proceeded to the second part of the Advanced Bionics framework.5

In analyzing the second part of the framework, the Board agreed with Petitioner and found that the Examiner materially erred in reviewing the references. Notably, the error stemmed from the arguments and expert testimony Patent Owner presented to the examiner during prosecution. For one reference, the Board found that "[Patent Owner's] characterization of the art" was "incomplete and inaccurate" and its expert improperly "downplay[ed]" certain disclosures while self-servingly exaggerated other portions.6 The Board concluded that, "[b]ut for this error, the Examiner would have better appreciated the disclosure" of the reference during prosecution.7 For two other references, the Board determined that Patent Owner "misled" the Examiner when considering whether a skilled artisan would have combined the references. Specifically, Patent Owner argued that a skilled artisan would have only considered certain sequences disclosed within each reference and such sequences could not be combined because they were mismatched. However, this ignored "express description[s] of other, more pertinent" sequences that did not face the same mismatching issues. In the Board's view, this caused the Examiner to "misapprehend[]" what the references disclosed.8 Based on these examiner errors, the Board declined to exercise its discretion under §325(d) to deny the petition.


As always, practitioners should use caution when characterizing references to the prior art during prosecution. Mischaracterizations may provide a basis for finding that the Office erred in a manner material to the patentability of the challenged claims under the Advanced Bionics framework.


1. See Advanced Bionics, LLC v. MED-EL Elektromedizinische Geräte GmbH, IPR2019-01469, Paper 6 at 8 (PTAB Feb. 13, 2020) (precedential); Becton, Dickinson & Co. v. B. Braun Melsungen AG, IPR2017-01586, Paper 8 at 17–18 (PTAB Dec. 15, 2017) (precedential as to § III.C.5, first paragraph)).

2. Samsung Bioepis Co, Ltd. v. Alexion Pharms., Inc., IPR2023-01070, Paper 6 at 17-20 (PTAB Oct. 13, 2023).

3. Id.

4. Samsung Bioepis Co, Ltd. v. Alexion Pharms., Inc., IPR2023-01070, Paper 9 at 61 (PTAB Dec. 19, 2023).

5. Id.

6. Id. at 63-64.

7. Id. at 65.

8. Id. at 66.

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