US 12091692

I'll search for docket and litigation information on this specific patent number, then compile the summary from the authoritative patent text I have.

Let me dig into the claims, the PTAB proceeding, and any Federal Circuit activity.

I have strong litigation context. Now let me pin down the claim set and check for any Federal Circuit activity.

US Patent 12,091,692 — Analyst Summary

Note on sources and scope: I worked from (a) the authoritative full text of US 12,091,692 retrieved from Google Patents (source URL in your message), and (b) live searches of USPTO/PTAB records, the D.N.J. docket, and secondary reporting. Searches returned materials dated as late as late September 2026, which post-date the "current date" stated in your prompt; where that creates a conflict I flag it. I have not verified verbatim claim language — see the explicit caveat in §4.

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1. Bibliographic data

2. Abstract (verbatim)

"Modified PH20 hyaluronidase polypeptides, including modified polypeptides that exhibit increased stability and/or increased activity, are provided. Also provided are compositions and formulations and uses thereof."

3. What the specification discloses

The patent is a structure/function "mutational map" of PH20 (sperm-surface, neutral-active hyaluronidase) built on Halozyme's MDASE™ platform. Its stated inventions fall into five buckets:

1. Modified PH20 polypeptides with increased stability — single or multiple amino acid replacements (up to ~150 differences; 1–75+ replacements enumerated) at positions defined by alignment to SEQ ID NO:3, giving resistance to denaturation by (a) elevated temperature (>~30 °C), (b) agitation, (c) low/no salt (<100 mM NaCl), and/or (d) denaturing excipients — especially phenolic preservatives (phenol, m-cresol, benzyl alcohol, parabens) at anti-microbially effective levels of ~0.05%–0.6% (w/v). The flagship example is F204P (replacement with P at position corresponding to position 204 of SEQ ID NO:3).
2. Modified PH20 polypeptides with increased hyaluronidase activity — e.g., ≥120%, ≥2-fold, up to ≥5,000% of unmodified activity.
3. Compositions/formulations — including combinations with a fast-acting insulin (lispro, aspart, glulisine; SEQ ID NOS:862–867 identified), NaCl ranges, buffers, surfactants (polysorbates, poloxamers, PEG/glycerin), pH ~7.0–7.6, and preservatives; with insulin-pump/insulin-pen and diabetes indications (A61P3/10).
4. Nucleic acids, vectors, host cells (e.g., CHO), and production methods.
5. Screening/evolution methods — methods for identifying or selecting a modified hyaluronan-degrading enzyme that retains activity under a denaturing condition (e.g., ≥5%/≥40% of activity versus non-denatured), including iterative screening of mutant libraries.

4. Overview of the independent claims — ⚠️ with explicit uncertainty

I do not have the verbatim claim text. The full-text extraction you supplied contains the specification's definitions section (the "Definitions" block) but not the claims. Everything below is reconstructed from (i) the specification's own definitions, (ii) the PTAB PGR record, and (iii) classification data, and must be verified against the USPTO PatentCenter claim listing before being relied on.

• Independent claim 1 — a composition-of-matter claim to a genus of "modified PH20 polypeptides." Plain-language: a PH20 (hyaluronidase) protein that differs from a reference PH20 by one or more amino acid replacements at positions identified by alignment to SEQ ID NO:3, where the underlying/reference PH20 is defined by a percentage-sequence-identity threshold (the specification recites thresholds of 68%, 85%, 91%, etc. against SEQ ID NO:3 or SEQ ID NO:7), and where the variant retains hyaluronidase activity / exhibits an altered (e.g., increased) stability property.
  • The PTAB's institution decision reportedly construed "modified PH20 polypeptide" broadly, consistent with the specification's own definition ("a PH20 polypeptide that contains at least one amino acid modification, such as at least one amino acid replacement … compared to a reference unmodified PH20 polypeptide").
  • Merck's petition challenged claim 1 as encompassing a genus of enormous size (in the parallel PGR over sibling US 12,060,590, Merck put the figure at >10¹¹² distinct modified PH20 polypeptides). The same genus-scope theory was asserted against the '692 patent.
• Additional independent claims — the specification supports, and the claim numbering (see below) is consistent with, independent claims to: (a) a pharmaceutical composition/combination (modified PH20 with a preservative and/or a fast-acting insulin); (b) a nucleic acid / vector / host cell; (c) a method of producing the polypeptide; and/or (d) a method of identifying/selecting a modified hyaluronan-degrading enzyme stable under a denaturing condition. I cannot confirm which of these are in independent form, or their exact scope.
• Claim count: the July 2025 statutory-disclaimer filing references claims numbered at least to 40 (see §5), implying roughly 40 claims in several independent groups.

5. Prosecution, disclaimer, and PTAB activity (USPTO)

• Statutory disclaimer (37 CFR 1.321(a)), filed 2025-07-24, patentee Halozyme, Inc., attorney Robert Smyth, Reg. No. 50801, covering "the following complete claim(s)": 3-4, 6, and 34-40 of US 12,091,692 (per the PTO filing document; charging Deposit Account 50-0310, $183.00 fee).
  • Discrepancy to flag: Venable's BiologicsHQ report on PGR2025-00046 states that, prior to institution, Halozyme "disclaimed multiple claims of the patent, including claims 3-4, 6, and 27-28." The word "including" plus the PTO form's "3-4, 6, and 34-40" can be reconciled as a single disclaimer of claims 3-4, 6, 27-28 and 34-40, but I could not confirm the consolidated list from a single authoritative document. Treat the exact disclaimed set as unverified.
• PGR2025-00046, Merck Sharp & Dohme LLC v. Halozyme, Inc. — petition filed April 29, 2025; instituted October 10, 2025. Grounds: obviousness, lack of written description, and lack of enablement. Per reporting, the PTAB agreed with Petitioner on the broad construction of "modified PH20 polypeptide" and found the evidence better supported Petitioner that the claimed genus is not adequately described; the PTAB did not find obviousness established at institution.
  • Docket activity shows the case is live into 2026: Patent Owner's Motion to Terminate (with several motions to seal and an opposition/reply cycle, Feb–Apr 2026), depositions, and requests for oral argument dated April 27, 2026. The apparent termination theory relates to the petitioner's real-party-in-interest/identity (documentation about Merck & Co., Inc. vs. Merck Sharp & Dohme LLC corporate structure). A final written decision would be expected on or about mid-October 2026 (12 months from institution).
• Context: the '692 patent is one of 14–15 Halozyme US patents challenged by Merck via PGR/IPR, all instituted, relating to Merck's subcutaneous pembrolizumab product (Keytruda Qlex™; pembrolizumab + berahyaluronidase alfa, developed with Alteogen, "ALT-B4"). The challenged set includes US 11,952,600; 12,018,298; 12,152,262; 12,123,035; 12,110,520; 12,060,590; 12,054,758; 12,049,652; 12,104,185; 12,037,618; 12,091,692; 12,077,791; 12,195,773; 12,264,345 (and a later petition on US 12,371,685). PTAB has issued final written decisions invalidating all remaining challenged claims of several siblings in 2026 (US 11,952,600 ~May 12, 2026; US 12,152,262 ~May 2026; US 12,018,298 ~June 8, 2026; US 12,110,520 ~September 1, 2026) on written-description/enablement grounds.

6. Litigation and CAFC 2026 check

• District court: Halozyme, Inc. v. Merck Sharp & Dohme Corp. (f/k/a Merck Sharp & Dohme LLC), Civil Action No. 2:25-cv-03179-ES-JRA (D.N.J.), complaint filed April 24, 2025 before Judge Esther Salas (Magistrate Judge Jose R. Almonte). Halozyme asserts 15 patents — expressly including US 12,091,692 — against SC Keytruda on MDASE™. Defendant substituted to Merck Sharp & Dohme LLC; initial scheduling conference October 20, 2025; docket activity continues into late 2025 and 2026. Halozyme also obtained a preliminary injunction in the Munich Regional Court (Dec 4, 2025) against Keytruda SC in Germany, based on EP 2797622.
• Federal Circuit (2026): ❌ No CAFC docket identified for US 12,091,692. My searches found no appeal at the U.S. Court of Appeals for the Federal Circuit naming this patent number as of the latest indexed materials. This is a negative finding, not a certification: the '692's own PGR (PGR2025-00046) had not yet reached a final written decision, so no appeal right has ripened for that proceeding. Related Halozyme patents with 2026 final written decisions are within their appeal windows and could appear at the CAFC, but I found no confirmed 2026 CAFC appeal for any of them either.

7. Points of uncertainty (stated explicitly rather than guessed)

1. Verbatim independent claim text was not available to me — the supplied full text omits the claims. §4 is an inference from the specification and the PGR record and must be verified in USPTO PatentCenter.
2. Exact total claim count and the complete disclaimed-claim list for the '692 patent are uncertain (PTO form says 3-4, 6, 34-40; secondary reporting says 3-4, 6, 27-28).
3. The >10¹¹²-polypeptide genus figure is documented in the PGR over sibling US 12,060,590, not confirmed as the figure used in the '692 petition.
4. No legal conclusion is drawn on validity, enforceability, infringement, or the Google Patents "expires 2034-11-28" adjusted-expiration estimate.
5. Date inconsistency: your prompt states a current date of April 26, 2026, but my searches returned items dated through approximately September 2026 (e.g., the September 1, 2026 '520 final written decision, reported September 2, 2026). I have reported the later materials rather than suppressing them.

Key source URLs: https://patents.google.com/patent/US12091692/en · https://ipverse.greyb.com/ptab-web/cases/case-details/PGR2025-00046 · https://biologicshq.com/ptab-grants-institution-of-four-pgrs-related-to-mercks-keytruda-qlex/ · https://dockets.justia.com/docket/new-jersey/njdce/2:2025cv03179/[566903](/patent/566903) · https://www.law.com/radar/card/halozyme-inc-v-merck-sharp--dohme-corp-57770840-1/ · https://ptacts.uspto.gov/ptacts/public-informations/petitions/[1557766](/patent/1557766)/

I'll search for litigation involving US patent 12091692 across the sources you mentioned.

Let me get more details on the specific cases.

Let me check the current status of the district court case and whether any other proceedings exist.

Based on my searches of patent-litigation sources (Unified Patents PTAB portal, the PTAB institution decision, the D.N.J. docket filings, Law.com Radar, and law-firm/industry trackers), US Patent 12,091,692 ("the '692 patent," PH20 polypeptide variants, formulations and uses thereof, assigned to Halozyme, Inc.) is involved in two US proceedings, plus related non-US counterpart actions. A summary of each follows.

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1. District court infringement action

Key points:

• The '692 patent is one of 15 patents-in-suit asserted against Merck's subcutaneous Keytruda (SC KEYTRUDA / KEYTRUDA QLEX, pembrolizumab + berahyaluronidase alfa). It appears as COUNT 10 — INFRINGEMENT OF U.S. PATENT NO. 12,091,692 in the complaint (available via the complaint PDF hosted at statnews.com).
• The complaint pleads § 271(a)/(b)/(c) infringement, willfulness (seeking enhanced damages), injunctive relief, and attorneys' fees under 35 U.S.C. § 285. All asserted patents are said to belong to a single family arising from Halozyme's MDASE™ technology.
• On May 15, 2025, the court entered a stipulated order substituting Merck Sharp and Dohme LLC as defendant, acknowledging service, and giving Merck 60 days to respond; Merck's answer was due/entered around July 14, 2025.
• No judgment or trial outcome has been reported; the case remains in its early stages (as of the most recent reporting, the only substantive filings were the complaint and Merck's answer).

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2. PTAB post-grant review

Key points:

• Grounds asserted: (1) lack of written description under § 112; (2) lack of enablement under § 112; and (3) obviousness over Halozyme's own U.S. Patent 7,767,429 (the '429 patent) in view of Chao et al. (2007). The PTAB instituted trial, finding the written-description/enablement evidence favored Petitioner (obviousness was contested).
• Before institution, Halozyme disclaimed several claims of the '692 patent (reported as claims 3–4, 6, and 27–28).
• Pending motion to terminate: Halozyme filed a Motion to Terminate arguing that Merck & Co., Inc. is an undisclosed real party-in-interest. Briefing and related motions to seal ran through February–April 2026 (e.g., Petitioner's Opposition filed Feb. 20, 2026; Petitioner's Supplemental Brief in Opposition filed Apr. 2, 2026; Patent Owner's Reply in Support filed Feb. 26, 2026). This appears unresolved.
• Under the PGR timeline, a final written decision would generally be due about 12 months after institution (i.e., on or around October 2026).

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3. Related (non-US) counterpart proceedings — for context only

These involve the European counterpart (EP 2 797 622, "the '622 patent") and its national validations, not US 12,091,692 directly, but they arise from the same Merck/Halozyme dispute over the same product:

• UK (High Court of Justice, Business and Property Courts, IP List (ChD)): Halozyme v. MSD — Halozyme counterclaimed for an injunction under EP '622 (and an additional patent); MSD filed revocation actions in the UK, France, Germany, and The Netherlands (Aug.–Sept. 2025). Reported decision: [2026] EWHC 121 (Pat) addressed whether Halozyme's statement of case on infringement adequately pleaded the functional "increased stability" feature.
• Germany: Halozyme filed a preliminary injunction under EP '622; Merck accepted service on Oct. 2, 2025.

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Summary

• Yes, litigation involving US 12,091,692 is known. There are two US proceedings:
  1. Halozyme, Inc. v. Merck Sharp and Dohme LLC, D.N.J. 2:25-cv-03179, filed April 24, 2025 (patent asserted as Count 10) — pending; and
  2. Merck Sharp & Dohme LLC v. Halozyme, Inc., PTAB PGR2025-00046, petition filed April 29, 2025, instituted October 10, 2025 — pending (with a pending real-party-in-interest motion to terminate).
• The Google Patents family page for US 12,091,692 flags the same two proceedings (PTAB PGR2025-00046 and the New Jersey case), consistent with the above.
• No final judgment or final written decision specific to the '692 patent was found. (Note: a separate final written decision invalidating a different Halozyme patent, US 11,952,600 in PGR2025-00003, issued on May 12, 2026 — that is not the '692 patent and should not be conflated with it.)

Caveats: I did not find a CAFC appeal or an ITC action naming US 12,091,692. Some sources contained minor inconsistencies (e.g., a Lexology note stating "24 April 2024" where the docket confirms April 24, 2025, and one U.S. case citation rendering "Merck Sharp & Dohme Corp." as "Merck Sharp & Dohme LLC"); where sources conflicted I relied on the primary docket/PTAB documents. Docket entries and PTAB papers should be verified against PACER and the USPTO PTAB portal for the most current status, since these matters are actively moving.

I'll research this patent's PTAB proceedings. The structured block says ODP shows none, but the patent page itself references PGR2025-00046 — let me investigate.

Let me get the institution decision details and trial timeline.

I have strong data. Let me pin down the institution decision's claim-level scope, the panel, and the current status as of today.

PTAB Proceedings — US 12,091,692 ("PH20 polypeptide variants, formulations and uses thereof")

Data-source note. The structured "PTAB proceedings on file" block (USPTO ODP) returns no AIA trials for this patent. That is wrong / stale. The patent's own Google Patents family record and multiple public dockets confirm an instituted PGR — PGR2025-00046 — on file. I have used the PGR as the canonical proceeding below and flagged the ODP discrepancy rather than repeating the "no activity" default. I could not retrieve a Final Written Decision for PGR2025-00046; none appears to have issued as of 2026-09-28 (statutory deadline ≈ 2026-10-10).

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Proceedings overview

One AIA trial is on file against US 12,091,692: PGR2025-00046 (Merck Sharp & Dohme LLC v. Halozyme Inc.), status "Pending - Instituted" (instituted 2025-10-10), with no claims yet invalidated by FWD, no settlement, and no Federal Circuit appeal. The Patent Owner has already statutorily disclaimed claims 3-4, 6, and 27-28 — those claims are gone regardless of how the PGR ends. Defensive posture: this is not a "hardened" patent and it is not a "claims-already-canceled" patent either — it is a live, broad-genus biotech patent under a § 112 written-description/enablement attack that the Board found "more likely than not" meritorious. A defendant should treat the asserted claim set as narrowing in real time (disclaimed claims already dead) and should not assume the remaining claims will survive to 2026-10-10.

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PGR2025-00046 — Merck Sharp & Dohme LLC v. Halozyme Inc. (Patent Owner RPIs: Halozyme, Inc. and Halozyme Therapeutics, Inc.)

• Type: Post-Grant Review (PGR) — not an IPR or CBM. (PGR is available because the '692 patent issued from an application filed 2021-05-21, App. No. 17/327,568, a continuation of a chain claiming priority to the '731 Application filed 2012-12-28; the Board's related decisions turn in part on whether the claims are entitled to that pre-AIA priority date.)
• Filed: 2025-04-29
• Status: "Pending - Instituted" (verbatim from the structured/portal data). Plain English: trial is open; no final merits decision yet.
• Judge panel: Michael A. Valek is confirmed as a panel member (Unified Patents PTAB case list for PGR2025-00046). Companion Halozyme-family orders list JEFFREY N. FREDMAN, SUSAN L. C. MITCHELL, CYNTHIA M. HARDMAN, and MICHAEL A. VALEK, but that order expressly states the judges are "paneled on various of the listed cases" — so I cannot confirm the full '692 panel with high confidence. Flagged as uncertain; verify on PTAB E2E.
• Petition grounds (challenged claims 1-40 overall):
  • Ground 1 — § 112(a) written description: claims 1-40 (and, per the petition's own headings, dependent claims 3-4, 6, 17-22, 26-40 specifically). Petitioner argued the claims recite a genus of modified PH20 polypeptides spanning on the order of 10⁶⁰–10¹¹³ species, while the specification exemplifies only single-substitution mutants plus a "prophetic," iterative make-and-test research plan.
  • Ground 2 — § 112(a) enablement: claims 1-40 (petition sub-headings split this into claims 1-2, 5, 7-16, 22-25 and dependent claims 3-4, 6, 17-22, 26-40). Petitioner invoked Amgen Inc. v. Sanofi — no guidance to separate active from inactive mutants across the claimed genus.
  • Ground 3 — § 103 obviousness: claims 1-2, 4-5, 7-26, and 29-40, over U.S. Patent No. 7,767,429 ("the '429 patent," Patentee's own) in view of Chao et al., "Structure of Human Hyaluronidase-1…," Biochemistry 46:6911-6920 (2007). Petitioner's theory targeted the single species M313K PH20₁₋₄₄₇, arguing a POSITA would have identified position 313 as a non-essential region and selected Lys as the most prevalent residue there.
• Institution decision: Instituted 2025-10-10. Pre-institution, Acting Director Coke Morgan Stewart denied Halozyme's request for discretionary denial (denying Fintiv-style and § 324(a)/§ 325(d) arguments, incorporating the analysis from PGR2025-00006, Paper 29 (Director 2025-06-12)) and referred the petition to the Board to decide institution on the merits. The Board then instituted trial. In the companion family institution decisions (e.g., '520, '652, '185), the Board found the evidence better supported Petitioner on both written description and enablement, and found Petitioner had not shown obviousness more likely than not. I could not independently confirm whether the '692 panel likewise declined institution on Ground 3; treat the § 103 ground's institution status as unverified and check the Institution Decision PDF (linked below).
• Final Written Decision: Not yet issued as of 2026-09-28. Statutory deadline under 35 U.S.C. § 326(a)(11) is 12 months from institution ⇒ approximately 2026-10-10. (Context: the first FWD in this coordinated campaign issued in PGR2025-00003 on 2026-05-12, holding all tried claims of U.S. 11,952,600 unpatentable — a different patent, but a signal on how the panels are resolving the shared § 112 record.)
• Settlement / termination: No settlement reported. Instead, Patent Owner has been litigating procedural termination: Halozyme filed a motion for additional discovery on unnamed real parties-in-interest (arguing Merck & Co., Inc. / MCI should have been named alongside Merck Sharp & Dohme LLC), completed briefing 2026-01-19, and then sought leave to file a motion to dismiss/terminate for failure to name all RPIs. The GreyB docket reflects a Board paper denying Patent Owner's motion for additional discovery. Petitioner maintains MCI is not an RPI and that Halozyme waived the issue. Outcome of the termination request is not confirmed in the sources retrieved.
• Appeal: None. No FWD, so no § 326 appeal clock has started. A CAFC appeal would run from the eventual FWD.
• Defensive value: Mixed but net favorable to a defendant right now. The Patent Owner has already surrendered claims 3-4, 6, and 27-28 by statutory disclaimer — those claims no longer exist, so any demand letter or infringement theory resting on them is dead on arrival. The remaining claims (1-2, 5, 7-26, 29-40) are all under an instituted § 112 written-description/enablement attack that the Board already found strong enough to try, with a decision due within days-to-weeks. Do not rely on § 315(e)/§ 325(e) estoppel yet — no estoppel attaches until a final written decision, and none has issued.

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Strategic summary

Claim status on 12,091,692. Using the sources retrieved:

• Statutorily disclaimed (gone): claims 3-4, 6, 27-28 (disclaimed before the 2025-10-10 institution decision). Statutory disclaimer under 35 U.S.C. § 253 has the effect of treating these claims as if they had never existed — they are not "narrowed," they are removed.
• Challenged and awaiting FWD: claims 1-2, 5, 7-26, 29-40 (the full originally-challenged set was 1-40; the disclaimed claims drop out). Claim 1 is the sole independent claim identified in the petition materials (a modified PH20 polypeptide having at least one substitution at position 313 plus permitted additional changes and a sequence-identity floor); claims 29-40 are the composition/method claims keyed to claim 1.
• Untested: none of substance — the entire surviving claim set is within the instituted trial. There is no claim of this patent that has been adjudicated patentable.

Estoppel landscape. Because no FWD has issued, no § 325(e)(2) estoppel has attached to Merck (and, for the family, no § 315(e)(2) estoppel on the parallel IPRs). That means for a different defendant considering its own PGR/IPR, the field is effectively open — in particular, the § 103 ground built on the '429 patent + Chao does not yet carry Petitioner-side estoppel barring others from raising it, and no prior art has been "adjudicated." Conversely, once a FWD issues (expected ~2026-10-10), Merck and its privies will be barred from re-asserting in district court any ground it raised or reasonably could have raised — which matters for the co-pending D.N.J. case. Practical point: a defendant weighing its own challenge should file before the '692 FWD issues, and should avoid duplicating Merck's exact § 112 framing if it wants to preserve a distinct theory.

Pattern signals.

• Same petitioner, coordinated campaign — not a one-off. Merck Sharp & Dohme LLC filed ~14 PGRs across Halozyme's modified-PH20 family beginning November 2024 (family patus: '600, '298, '262, '035, '520, '590, '758, '652, '185, '618, '791, '345, '773, plus the '692), and later a set of IPRs. This is a deliberate clearing action tied to Merck's Keytruda Qlex™ (pembrolizumab + berahyaluronidase alfa-pmph, approved September 2025), which uses a partner (Alteogen) PH20 enzyme, ALT-B4, not a Halozyme enzyme.
• Patent Owner is fighting hard on procedure, not merits concessions. Halozyme has repeatedly tried to (a) defeat institution on discretionary grounds (denied by the Acting Director), and (b) knock out the petitions on unnamed-RPI grounds (§ 322/§ 315-type standing/RPI arguments), with extensive discovery motion practice. It has also statutorily disclaimed claims across the family rather than defend them.
• No defensive aggregator. Despite the Google Patents page pointing to "Unified Patents PTAB Data," that is a data attribution, not an ownership/party fact. The petitioner of record is Merck Sharp & Dohme LLC itself; Unified is not in the chain as a filer. Do not describe this as a Unified Patents challenge.
• Related litigation: Halozyme, Inc. v. Merck Sharp & Dohme Corp., No. 2:25-cv-03179 (D.N.J.) — Halozyme asserts the '692 and related patents; Petitioner has argued the FWD will land ~4 years before a D.N.J. trial date (projected ~May 2030) and that institution supports staying the litigation. Also note the Google Patents "PTAB case PGR2025-00046 filed (Pending – Instituted)" entry and the New Jersey case cross-reference are consistent with the above.

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Recommended next steps

1. For a defendant being asserted on this patent today:
   • Immediately identify which claims are actually in play. Claims 3-4, 6, 27-28 are disclaimed and cannot be asserted. If any demand, complaint, or infringement contention chart cites them, that portion is meritless — push back now.
   • Watch 2026-10-10. The PGR2025-00046 FWD is due on/about that date. If the panel follows the PGR2025-00003 outcome (2026-05-12: all tried claims unpatentable under § 112), the surviving claim set could be canceled in full within days. Do not finalize an invalidity/non-infringement strategy on claims 1-2 or 5 without building in the FWD contingency.
   • Link to the decision record: Institution Decision PDF — https://biologicshq.com/wp-content/uploads/2025/10/PTAB-PGR2025-00046-Institution-Decision.pdf ; docket hub — https://ipverse.greyb.com/ptab-web/cases/case-details/PGR2025-00046 ; Unified Patents portal page — https://portal.unifiedpatents.com/ptab/case/PGR2025-00046 . Verify current status and any FWD on PTAB E2E / PTAB Center and, once an FWD issues, on CourtListener (no CAFC docket exists yet because there is no appealable decision).
   • Estoppel timing: because no FWD has issued, there is no § 325(e)(2) bar yet. If you are considering your own IPR/PGR, filing pre-FWD is the cleanest path and avoids any risk of being treated as a privy of Merck.
2. If the FWD issues and cancels claims: link to it directly and quote the disposition at claim-level ("all of claims 1-2, 5, 7-26, and 29-40 unpatentable" — exact wording pending), and note that statutory disclaimer already eliminated 3-4, 6, 27-28.
3. If the FWD is appealed: docket at the Federal Circuit; issues would be the § 112 written-description/enablement holdings (and, if institution was partial, any non-instituted § 103 ground is not appealable by Patent Owner in the usual course).
4. Trial-stage milestones for PGR2025-00046: institution 2025-10-10; oral hearing per the family's coordinated schedule (the first tranche heard 2026-03-02; the '692 hearing date is not confirmed and may be staggered); FWD due ≈ 2026-10-10 (statutory 1-year deadline from institution).

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Verification caveats (read before relying)

• ODP return is stale. The structured "no AIA trial proceedings" result should be treated as an indexing gap, not a substantive finding; PGR2025-00046 is confirmed on file.
• Not independently confirmed from primary source in this pass: (i) the full '692 panel composition; (ii) whether the § 103 ground was instituted or denied for the '692 (the family pattern disfavors obviousness, but I did not confirm the '692 disposition); (iii) the outcome of Halozyme's RPI/termination request in the '692 (its additional-discovery motion was denied); (iv) whether an FWD has issued in the last few days. Each should be checked against PTAB E2E before it is cited in a filing.

I'll verify the assignment record and the surrounding litigation before writing anything.

Let me check the assignment reel/frame specifics and Halozyme's corporate history.

Let me try to pin down reel/frame numbers and the litigation/asserter context.

US 12091692 — Ownership & Assignment Reconstruction

Scope note / evidentiary caveat up front. I could not obtain the Assignment Center reel/frame numbers or the recording correspondent field for this patent in this session — the USPTO Assignment Center and assignment.uspto.gov interfaces are not directly queryable with the tools available here, and no mirror surfaced the reel/frame strings for the Halozyme recordings. Everything below is drawn from the Google Patents legal-events block (which mirrors the same underlying USPTO assignment data), the PTAB public record, the D.N.J. docket record, and SEC/press disclosures. I have not substituted plausible-looking reel numbers. Treat reel/frame and correspondent as open items to be confirmed by a direct Assignment Center lookup at https://assignmentcenter.uspto.gov/.

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Inventors

Unusual patterns. Two things stand out, and neither is an NPE tell:

1. Split assignment routing. Three inventors (Wei, Zhao, Connor) assigned to the parent (Halozyme Therapeutics, Inc.) while one (Shepard) assigned to the operating subsidiary (Halozyme, Inc.), which then received a confirming assignment from the parent. This is a title-curative structure — inventors papered to whichever Halozyme entity their employment/consulting relationship ran to, followed by a clean-up assignment into the entity that holds the portfolio. It is not evidence of a licensing shell; the terminal assignee is an operating entity.
2. A ~9.5-year gap between invention date and the application at issue. Priority is the 2011-12-30 provisional US 61/631,313; application 17/327,568 was filed 2021-05-21 as a continuation in the chain back through 13/694,731 (now US 9,447,401). All four original inventors are still listed on the 2021 continuation — no inventor departures, no substitute inventors, no "all inventors gone within 12 months" pattern.

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Original assignee

Halozyme, Inc., 12390 El Camino Real, San Diego, CA 92130 — the wholly owned operating subsidiary of Halozyme Therapeutics, Inc. (NASDAQ: HALO), the publicly traded parent. Both are named as real parties-in-interest in the PGR record ("Patent Owner identifies Halozyme, Inc. and Halozyme Therapeutics, Inc. as the real parties-in-interest," PGR2025-00017 Final Written Decision).

• Primary line of business: biopharmaceutical drug-delivery technology. Its ENHANZE® platform (rHuPH20, a recombinant human PH20 hyaluronidase) is licensed to Roche, Takeda, Pfizer, Janssen, AbbVie, Lilly, BMS, argenx, ViiV, Chugai and others. It also develops and commercialises drug-device combination products (Antares acquisition, closed 2022-05-24, ~$960M).
• Ships product embodying the technology: yes — Hylenex® recombinant (hyaluronidase human injection) and XYOSTED® auto-injector products, plus ten commercialised ENHANZE-partnered products. Note the nuance Merck presses: the asserted MDASE-family patents do not read on the unmodified rHuPH20 in Hylenex; the '692 claims are directed to modified PH20 variants (e.g. residue-313 substitutions). So Halozyme is unambiguously an operating company practicing the PH20 platform, even though whether any single shipped product falls inside claim 1 of the '692 patent is contested.
• Current status: operating and profitable. FY2024 revenue in the billion-dollar range and positive net income since 2017. No bankruptcy, no dissolution, no restructuring of the portfolio into a licensing vehicle.

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Assignment timeline

Three recorded assignments, all executed/recorded 2021-05-24 — i.e. three days after the 2021-05-21 filing of application 17/327,568. There are no post-issuance assignments in the record. Halozyme, Inc. is the owner of record as of 2026-09-28.

• 2021-05-24 (executed) / recorded 2021-05-24 — Reel/frame not retrieved (see scope note)

  • Conveyance: Assignment (inventor-to-company, filing-contingent)
  • Assignor: Robert James Connor; Ge Wei; Qiping Zhao
  • Assignee: Halozyme Therapeutics, Inc.
  • Correspondent: not retrieved
  • Context: routine employment/obligation assignment perfecting title at filing.

• 2021-05-24 (executed) / recorded 2021-05-24 — Reel/frame not retrieved

  • Conveyance: Assignment
  • Assignor: H. Michael Shepard
  • Assignee: Halozyme, Inc.
  • Correspondent: not retrieved
  • Context: founder/former-officer assignment of retained rights running directly to the operating subsidiary.

• 2021-05-24 (executed) / recorded 2021-05-24 — Reel/frame not retrieved

  • Conveyance: Assignment (internal reorganisation / title confirmation)
  • Assignor: Halozyme Therapeutics, Inc.
  • Assignee: Halozyme, Inc.
  • Correspondent: not retrieved
  • Context: intra-group clean-up transfer vesting the entire right, title and interest in the operating subsidiary that holds the PH20/MDASE portfolio. Not a sale, not a securitisation, not an asserter transfer — the two entities share a corporate family and both were named as real parties-in-interest in the resulting PTAB proceedings.

For context on the surrounding prosecution correspondent (distinct from the assignment-recording correspondent): the issue notice of 2024-08-28 lists Morgan, Lewis & Bockius LLP (PH), 2222 Market Street, Philadelphia, PA 19103, docket 063995-01-5105-US04, and attorney Robert Smyth (Reg. No. 50,801) signed a 37 CFR 1.321(a) disclaimer for Halozyme, Inc. on 2025-07-24. A single corporate firm handling a large continuation family is ordinary and is not a repeat-correspondent NPE signal.

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Timeline diagram

timeline
    title Ownership of US 12091692
    2011 : Priority application filed
    2021 : Continuation filed by Halozyme
         : Inventors assign rights to Halozyme
         : Parent confirms title to Halozyme Inc
    2024 : Patent issued to Halozyme Inc
    2025 : Halozyme sues Merck in New Jersey
         : Merck files PGR2025-00046
         : PTAB institutes the PGR
    2026 : Board order on motion to terminate

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NPE / troll-pattern signals

1. Shell-entity transfer — NOT PRESENT. No LLC, no "IP/Holdings/Ventures" assignee appears anywhere in the chain. The terminal assignee since 2021-05-24 is Halozyme, Inc., a named real party-in-interest with a San Diego operating address, and the parent is SEC-reporting. No single-purpose entity, no registered-agent address, no Delaware/Texas shell LLC.

2. Known asserter in the chain — NOT PRESENT. Nothing in the chain matches Acacia, Marathon, IV, IPNav, Wi-LAN, Conversant/Mosaid, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, or a Spangenberg entity. The only third-party directory classification I can cite is Unified Patents' PTAB case list, which classifies the owner of record as "Halozyme Inc — Operating Company" and the challenger as "Merck Sharp & Dohme LLC — Large Operating Company."

3. Repeat correspondent across the chain — UNCL EAR / NOT ASSESSABLE. I could not retrieve the recording correspondent for any of the three 2021-05-24 entries; the reel/frame lookup would be required. The only correspondent data I can cite is the prosecution firm of record (Morgan, Lewis & Bockius LLP, per the 2024-08-28 issue notice) and Robert Smyth's 2025-07-24 disclaimer. One firm appearing on a corporate family is not a finding; I record this as a gap, not as evidence either way.

4. Cascading transfers — NOT PRESENT. All three recordings bear the same execution and recording date (2021-05-24) and all terminate at Halozyme, Inc. This is a one-day chain-of-title perfection cluster at filing, not serial transfers through chained LLCs. There have been zero further ownership events in the ~5 years since, through issuance (2024-09-17) and the onset of litigation (2025-04-24).

5. Pre-litigation transfer — NOT PRESENT. The last ownership event precedes the first infringement suit by almost four years: 2021-05-24 assignment vs. complaint filed 2025-04-24 in Halozyme, Inc. v. Merck Sharp & Dohme LLC, No. 2:25-cv-03179 (D.N.J.) (originally captioned against Merck Sharp & Dohme Corp.; parties substituted by stipulation in 2025). Nothing was moved into position to enable assertion — the owner was already the owner.

6. Bankruptcy fire-sale — NOT PRESENT. No Chapter 7/11, no sale motion, no secured-party assignment. Halozyme was cash-generative and buying back stock throughout the relevant period (including a completed $550M repurchase programme and the 2022 Antares acquisition).

7. Privateering — NOT PRESENT. Halozyme asserts in its own name and on its own behalf: Halozyme, Inc. is the plaintiff of record and the patent owner of record, and it is the entity that (per Merck's briefs) offered MSD a licence in March 2025 before filing suit in April 2025. There is no NPE fronting the campaign. If anything the alignment is the mirror image of privateering — the large operating company (Merck/MSD) is the challenger, having filed PGR petitions on 14–15 Halozyme patents between November 2024 and June 2025 (PGR2025-00046 over the '692 patent was filed 2025-04-29, five days after the district court complaint, and instituted 2025-10-10).

8. Defensive aggregator (anti-NPE) — NOT PRESENT. The chain does not terminate at RPX, AST, LOT, Unified Patents or OIN. It terminates at the practising owner, which is using the portfolio offensively.

Post-issuance litigations / contests worth logging alongside the ownership record: PGR2025-00046 (Merck Sharp & Dohme LLC v. Halozyme, Inc., instituted 2025-10-10; Board order on Halozyme's motion to terminate dated 2026-05-12); D.N.J. 2:25-cv-03179; parallel German proceedings in which Halozyme obtained a preliminary injunction (December 2025). Note also that a sibling patent in the family, US 11,952,600, was held unpatentable for lack of written description and enablement on 2026-05-12 — relevant to the commercial durability of this family, though not to ownership.

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Verdict

Operating-company assertion.

Justification: the entire recorded chain consists of three 2021-05-24 assignments that start with the four named inventors and end at Halozyme, Inc., the operating subsidiary of NASDAQ-listed Halozyme Therapeutics, Inc., with no subsequent transfer of any kind through issuance on 2024-09-17 and beyond. The owner of record is the plaintiff asserting US 12,091,692 (along with 14 sibling patents) against Merck Sharp & Dohme in D.N.J. 2:25-cv-03179, filed 2025-04-24, after Halozyme offered a commercial licence in March 2025; Unified Patents independently classifies the patent owner as an "Operating Company." The only NPE-adjacent feature in the file — an assignment footprint dated within three days of filing — is a title-perfection cluster at the original assignee, not a transfer to an asserter.

Verify at: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (search patent number 12091692) · Google Patents legal events — https://patents.google.com/patent/US12091692/en · D.N.J. docket — https://portal.unifiedpatents.com/litigation/New%20Jersey%20District%20Court/case/2%3A25-cv-03179 · PTAB — https://portal.unifiedpatents.com/ptab/case/PGR2025-00046

Open items for a follow-up pull: (i) reel/frame for each of the three 2021-05-24 recordings; (ii) the recording correspondent on those three entries, to run the repeat-correspondent test against other Halozyme-family patents; (iii) confirmation whether Halozyme's 2025-07-24 statutory disclaimer touched the '692 claims (a disclaimer exhibit appears in the PGR record as EX2003), since that would affect the practical scope of the asserted right even though ownership is unchanged.

I'll pull the reference/citation record for US 12,091,692 from multiple sources (Google Patents patent citations, USPTO PatentCenter "References Cited," and the PGR petition's prior-art statement), then map each reference to claim scope.

Let me pull the front-page "References Cited" from the patent PDF itself and the Justia/FreePatentsOnline entries, which reproduce the citation list.

The search layer isn't surfacing the '692 front-page citation list directly. Let me target the citation-bearing pages (Justia, FPO, Google Patents "Citations" tab) and the PGR petition's prior-art statement.

Method note and a hard limitation up front

I searched for the front-page "(56) References Cited" list of US 12,091,692 — i.e., the examiner-cited U.S. patent documents, foreign patent documents and non-patent literature that appear on the printed patent. I could not retrieve that list from a primary source in this session. Targeted searches of the citation-bearing pages returned: (a) the (56) block of other patents entirely (US 11,636,870; US 11,344,413; USD 777,079; US 11,368,670) — which are not the '692 patent and must not be attributed to it; (b) family/priority listings for the Halozyme continuation chain; and (c) the PGR papers. No Google Patents "Citations" tab content, no Justia/FPO (56) reproduction, and no USPTO PatentCenter "References Cited" extract for 12,091,692 was returned.

Therefore I am not going to reconstruct a plausible-looking (56) list. Everything below is limited to prior art that is documented in the record I do have: the prior art actually pleaded in the instituted post-grant review, the specification's own background citations, and the same-family/co-pending documents. Where I am uncertain I say so.

Verification paths for the true (56) list (should be pulled before any filing relies on it):

• Patent PDF front page, col. 1–2 — patentimages.storage.googleapis.com/.../US12091692.pdf
• USPTO PatentCenter → Application 17/327,568 → "References Cited"
• Google Patents → https://patents.google.com/patent/US12091692/en → "Citations" section
• USPTO Patent Public Search (ppubs) full-text view of the grant

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A. The prior art that the record treats as relevant

A.1 The references actually asserted — PGR2025-00046 (Merck Sharp & Dohme LLC v. Halozyme, Inc.)

This is the single most reliable prior-art signal available, because it reflects what a sophisticated challenger with full access to the file history selected as the closest art, and the Board's decision to institute on it.

The critical negative inference: Merck pleaded the '692 claim 1 as obvious, not anticipated, over the '429 patent. Petitioner's own theory was that a POSITA "would have identified position 313 as a non-essential region and selected Lys as the most prevalent residue there" — i.e., the single species M313K PH20₁₋₄₄₇ was the target of a modification rationale. If the '429 patent had disclosed M313K outright, the ground would have been written as anticipation. This is persuasive record evidence that no cited reference anticipates claim 1 under § 102.

A.2 Same-family / co-pending documents — not § 102 prior art, but the priority-date hinge

All of these share the 2011-12-30 priority claim of the '692 patent (per the Google Patents family/priority listing for US12371685 and siblings):

• US 2014/0178330 A1 — "PH20 Polypeptide Variants, Formulations and Uses Thereof" (Halozyme pre-grant publication in the same chain; published 2014-06-26)
• WO 2013/102144 A2 (PCT/US2012/072182; published 2013-07-11)
• EP 3 130 347 A1 — same title (published 2017-02-15)
• JP 6422933 B2 — same title
• The U.S. continuation cluster: US 9,447,401; 10,865,400; 11,041,149; 11,066,656; 11,952,600; 12,018,298; 12,037,618; 12,049,652; 12,054,758; 12,060,590; 12,077,791; 12,104,184; 12,104,185; 12,105,120; 12,123,035; 12,195,773; 12,264,345; 12,371,685; 12,652,345… (the family listing retrieved from the sibling US 12,371,685 page, all bearing priority 2011-12-30)

Why these matter for § 102: as long as the '692 claims are entitled to 2011-12-30, these are same-family documents and are not prior art under either pre-AIA § 102 or AIA § 102(a)(2) (common-ownership / same-inventive-entity exceptions and, for the U.S. continuations, § 102(b)(2)(C)-type considerations apply). But if priority fails for a given claim — exactly the question the Board has been litigating across this family — then the 2013–2017 Halozyme publications themselves become § 102(a)(1)/(a)(2) art against that claim, and they are the most dangerous § 102 references in existence for this patent, because they disclose the same mutant map.

A.3 Background art cited by the specification itself (from the authoritative full text you supplied)

These are cited in the '692 specification and are therefore unquestionably "of record" in the patent's own disclosure, even though I cannot confirm they appear in the printed (56) block:

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B. § 102 mapping — which claims each reference could potentially anticipate

Working claim scope (per the previously generated sections, which I treat as authoritative but flag as unverified against the printed claims): claim 1 is the sole independent claim — a modified PH20 polypeptide having at least one substitution at residue 313 (including K), with a permitted number of additional changes and a sequence-identity floor; claims 29–40 are the composition/method claims keyed to claim 1; claims 3–4, 6, 27–28 have been statutorily disclaimed (the PTO disclaimer form additionally recites 34–40 — flagging that unresolved discrepancy from the earlier section).

Bottom line on § 102: on the record available, no citation to US 12,091,692 is an anticipatory reference. The asserted theory against the '692 patent is § 112(a) written description and enablement (instituted) with a § 103 backstop — not § 102. That is consistent with the earlier-generated sections, which report the Board finding the § 112 evidence "better supported Petitioner" while the § 103 ground was contested.

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C. The priority-date question that governs everything above

This is the single most important § 102 judgment call on this patent, and it cuts across all the references:

• The PGR was filed as a post-grant review rather than an IPR — the AIA trial vehicle reserved for patents subject to the first-inventor-to-file provisions. That is consistent with at least one claim not being cleanly entitled to the 2011-12-30 priority date, and the earlier sections note that the Board's related family decisions "turn in part on whether the claims are entitled to that pre-AIA priority date."
• If a claim is not entitled to 2011-12-30, the governing provision is AIA § 102(a)(1)/(a)(2) and the sheer volume of intervening Halozyme publications (2013–2017) and the 2012-filed sibling applications becomes § 102 art.
• If the claim is entitled to 2011-12-30, the governing provision is pre-AIA § 102(a)/(b)/(e)/(g), and PA-1 and PA-2 are § 103 references under pre-AIA § 103(a) only.

I could not resolve which regime the Board applied to the '692 claims specifically — verify against the Institution Decision (linked in the earlier PTAB section: https://biologicshq.com/wp-content/uploads/2025/10/PTAB-PGR2025-00046-Institution-Decision.pdf).

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D. Contradiction I am obligated to flag

The two previously generated sections are not consistent on independent claim 1:

• "Patent summary" §4 describes independent claim 1 as a genus of modified PH20 polypeptides with at least one replacement at a position identified by alignment to SEQ ID NO:3, where the reference PH20 is defined by a percentage-identity floor (68%/85%/91%).
• "PTAB challenges" describes claim 1 as "a modified PH20 polypeptide having at least one substitution at position 313 plus permitted additional changes and a sequence-identity floor."

These are reconcilable (a genus claim whose characterizing limitation is a residue-313 substitution), but they are not the same statement, and the difference matters enormously for § 102/§ 103 — a claim limited to position 313 is far narrower than one covering all of the enumerated positions in the specification. The complaint excerpt I retrieved independently supports the residue-313 reading: "the '400 patent, the '149 patent, the '298 patent, the '345 patent, and the '692 patent have claims directed to modified PH20s with modifications to residue 313… including lysine (K)." It simultaneously shows the family is partitioned by residue — '400/'656/'618/'791 → residue 309; '400/'149/'298/'345/'692 → residue 313; '758/'262 → residue 317 — which is consistent with each continuation being narrowed to a distinct residue set. I still cannot confirm verbatim claim 1. Until that is pulled from PatentCenter, the § 102 claim-by-claim table in §B is indicative, not definitive.

(Also flagged from the earlier section and unresolved here: the identity of the "'149 patent" in the complaint grouping, which is not among the 14–15 patents listed in the MSD PGR campaign. I am not going to guess its number.)

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E. What I would do next

1. Pull the actual (56) block from PatentCenter / the grant PDF (paths in the method note) — this is the specific thing the task asked for and the one thing I could not deliver from primary source.
2. Pull claim 1 verbatim and confirm the residue-313 limitation, to convert §B from indicative to definitive.
3. Pull the PGR2025-00046 Petition's prior-art statement (PTA cites the Fintiv-relevant "total pages" note as priority-art information) to capture any reference Merck cited but did not institute on — those are the references a different defendant could still use, free of estoppel (no FWD has issued, so no § 325(e)(2) estoppel has attached yet).
4. Watch the FWD due ≈ 2026-10-10. If the panel follows PGR2025-00003 (US 11,952,600 held unpatentable 2026-05-12) and the other 2026 family decisions, a § 102 analysis of the surviving claims may become moot.

Version note: this task states a current date of April 26, 2026, whereas the system date is 2026-09-28 and retrieved materials run through September 2026. Consistent with the earlier sections, I report the later-dated material rather than suppressing it, and flag the conflict.

I'll verify a few open items flagged in the prior-art section — specifically the claim-1 language and whether the §103 ground was instituted — before building the obviousness analysis.

Let me try to pin down whether the §103 ground was actually instituted, and how the family's FWDs resolved the obviousness ground.

Obviousness Analysis — US 12,091,692 B2 under 35 U.S.C. § 103

Scope and relationship to the prior sections. This builds directly on the Prior Art, PTAB challenges, and Litigation sections above. Two things in those sections are now resolved by primary-source documents I retrieved in this pass, and one is refined:

• Claim 1's verbatim text is now confirmed (the earlier §4 reconstruction was in the right zone but not the right position feature — it is position 313, not the specification's flagship F204P). See §1.
• The disclaimed-claim set is now reconciled. The Institution Decision lists the challenged claims as 1, 2, 5, 7–33, and the Ground 3 table as 1, 2, 5, 7–26, 29–33. That directly confirms the disputed disclaimers: 3, 4, 6, 27, 28, 34–40 are gone (the union of the PTO form's "3-4, 6, 34-40" and Venable's "3-4, 6, 27-28"). The "discrepancy to flag" in the earlier PTAB section is thereby resolved in favor of the union. Source: PGR2025-00046 Institution Decision.
• Contradiction to flag. The earlier litigation summary said the Board "did not find obviousness established at institution." The Institution Decision actually contains a dedicated merits section, "C. Asserted Obviousness over the '429 Patent and Chao — 1. Petitioner's Position," which is not the structure of a ground the Board refused to reach. I treat the §103 ground as addressed on the merits and most likely instituted, and flag that the earlier framing should be reconciled against the decision's concluding order.

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1. What must be proved obvious

Claim 1 (verbatim, from the Institution Decision, quoting Ex. 1001 at 317:19–40):

1. A modified PH20 polypeptide, comprising one or more amino acid modifications in an unmodified PH20 polypeptide, wherein:

• the unmodified PH20 polypeptide consists of the amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7 and 32-66;
• amino acid modifications are selected from the group consisting of amino acid replacement(s), deletion(s), and/or insertion(s);
• the modified PH20 polypeptide comprises a modification at a position corresponding to position 313 with reference to amino acid positions of SEQ ID NO:3;
• corresponding amino acid positions are identified by alignment of the PH20 polypeptide with the polypeptide having the amino acid sequence of SEQ ID NO:3;
• the modified PH20 polypeptide has at least 91% sequence identity to the amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7 and 32-66.

Four observations drive the whole §103 analysis:

1. Claim 1 is purely structural. It recites no hyaluronidase-activity floor, no increased stability, and no phenolic-preservative resistance. The specification's definitions describe modified PH20s as retaining activity, but that requirement is absent from the claim language as reproduced by the Board. Any obviousness theory must therefore be evaluated against a structural genus, not a performance genus.
2. The position-313 feature is the only narrow element. The ≥91% identity floor is generous — for a 447-residue protein that permits roughly 40 additional substitutions, plus deletions and insertions. So claim 1 covers M313K PH20₁₋₄₄₇ expressly, and covers an astronomically large set of multiply-modified members (Petitioner's figure in this family runs 10⁴⁹–10¹¹³).
3. The specification's headline example, F204P/phenolic-preservative stability, is not the claimed feature. This is a genuine internal mismatch worth flagging: the earlier Patent summary correctly described the spec's stability/preservative thrust, but the '692 claims are the position-313 family member (the sibling petitions target 307, 309, 312, 317, 320, 324). The specification's preservative data therefore supplies no nexus to claim 1 unless a dependent claim captures it.
4. Live claim set: 1–2, 5, 7–33 (subject to the FWD). Claims 3–4, 6, 27–28, 34–40 are statutorily disclaimed and cannot be asserted or sustained.

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2. Legal framework

Governing standard. Graham v. John Deere factors, applied through KSR Int'l Co. v. Teleflex, Inc., 550 U.S. 398 (2007): scope and content of the prior art; differences between the art and the claims; PHOSITA level; and objective indicia. The Board adopted Petitioner's POSITA definition — an advanced degree (Ph.D.) plus post-doctoral experience in protein chemistry/biochemistry/biophysics, with familiarity with protein structure, folding, sequencing/alignment, modeling software, recombinant production, and functional assays (Institution Decision, §VII).

The three pressure points in this art. For genus claims to engineered proteins, §103 turns on:

Prior-art status is not in dispute. US 7,767,429 issued 2010-08-03 and Chao published 2007 — both more than one year before the earliest priority (2011-12-30), so both are §102(b) art under pre-AIA law and §102(a)(1) art under the AIA if Merck's priority attack succeeds. Common ownership does not rescue Halozyme: the pre-AIA §103(c) and AIA §102(b)(2)(C) carve-outs reach only §102(e)/(f)/(g) and §102(a)(2) art respectively, not §102(b) printed publications. The '429 is Halozyme's own patent and remains fully available for §103.

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3. The primary combination: US 7,767,429 + Chao (2007)

This is the only §103 combination actually pleaded (Ground 3), and its architecture is a three-step obviousness case targeting one species that falls inside the claim.

3.1 Element-by-element mapping

3.2 The three motivations asserted

1. The '429's express suggestion. The '429 is not merely a reference of general background — it teaches the type of modification (single amino-acid substitution), the location class (non-essential regions), the substrate sequence (PH20₁₋₄₄₇), and the result (equivalents that do not substantially alter activity). Under KSR, express guidance in a patentee's own prior patent that a class of modifications yields equivalents is a paradigm "design incentive" teaching.
2. Chao supplies the missing map. A POSITA guided by the '429's suggestion to modify non-essential regions would consult the state of the art on PH20/hyaluronidase structure to find those regions. Chao supplies exactly that: conserved active-site residues, the Hyal-EGF domain, and a structure-based alignment delimiting essential from non-essential spans. This is the classic "reference reasonably pertinent to the particular problem" combination rationale (KSR; In re Khan line).
3. Residue prevalence → obvious choice of substituent. Dr. Park's 88-protein alignment showed wild-type Met at ~14% of positions corresponding to 313, with Lys the most prevalent amino acid there. A POSITA selecting a replacement would look to the amino acids evolution has tolerated at that position; K being the most common makes M313K an obvious candidate.

3.3 Reasonable expectation of success

Petitioner's expectation-of-success evidence is grounded in the prior art in three layers: (a) the '429's own statement that single substitutions in non-essential regions generally do not substantially alter activity; (b) PH20's own patentee admissions during prosecution of the '429 — Merck expressly argues "Patentee Cannot Contradict Its Past Representations to the PTO" (Pet. §V.B.5(a)); and (c) a PH20 structural model indicating position 313 tolerates lysine.

3.4 Why this theory is weak — and how the Board has already treated it

Halozyme's POPR attacks the combination at each joint, and the Board has already accepted a materially identical attack in a sibling final written decision:

• No reason to modify a working enzyme. As Halozyme put it: "Merck's Petition provides no reason why a POSA would have been motivated to make an amino acid substitution(s) in non-essential regions of PH20… when Merck's cited art suggests that doing so would be pointless ('without altering the biological activity')." The '429's teaching that such substitutions are neutral is, on this reading, a teaching away from making them for any purpose. This is the Metalcraft/Belden failure mode.
• The '429 identifies no non-essential residues. The whole gap (which residues are "non-essential") is filled by Chao — an alignment of other human hyaluronidases, not PH20.
• "Non-conserved ≠ non-essential." Halozyme's central merits argument: Merck "falsely equat[es] non-conserved residues as 'non-essential.'"
• M313K is not a conservative substitution. Halozyme's strongest unstated point: the '429's teaching is expressly about conservative substitutions, yet Met→Lys is nonpolar→basic. That mismatch cuts against the "same class of modification" rationale.
• Hindsight / declarant-driven. Halozyme argues the ten other parallel petitions use the identical art and the identical two declarants to reach nine different target positions (307, 309, 312, 313, 317, 320, 324) — a pattern Halozyme characterizes as hindsight: "[o]nly hindsight—provided by counsel—led Park and Hecht to position 307."
• PTAB precedent in this family. In PGR2025-00017 (US 12,110,520), the Board's FWD invalidated all claims under §112 but held the §103 ground ('429 + Chao) "Not shown Unpatentable" for every challenged claim. See PTAB-PGR2025-00017 FWD (outcome table: §112 written description and enablement → unpatentable; §103 → not shown). That is the single most probative data point for predicting PGR2025-00046: the Board has already rejected this exact combination on the merits once.
• §325(d) overlay (Board only). The '429 was cited/considered during prosecution and discussed in the specification; Chao is argued cumulative to Stern, Zhang, and Arming, all examiner-considered. That is a discretionary-denial argument, not a merits argument — and it has no application in district court, where §325(d) does not bind.

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4. Alternative and reinforcing combinations

Caveat up front: the following are my analytical constructions, not pleaded grounds, and each needs claim-chart verification against the specific reference disclosure.

Combination A — '429 + Chao + Stern (2006). Stern supplies an independent alignment of five human hyaluronidases against bee-venom hyaluronidase with secondary-structure annotation. Adding Stern makes the "identify position 313 as non-essential" step available from two independent sources and removes any argument that Chao's teaching is isolated. Trade-off: Stern was before the examiner, so this strengthens the merits while weakening any Board-side §325(d) posture. In district court, that trade-off is irrelevant.

Combination B — '429 + Chao + Zhang (2009) + Arming (1997). Zhang supplies HYAL1 active-site/EGF-domain residue assignments; Arming supplies empirical PH-20 mutagenesis showing which regions tolerate change. Used together, they let a challenger assert that a POSITA had both the structural map (Chao/Zhang) and the experimental mutagenesis precedent (Arming) needed to pick and validate a non-essential position.

Combination C — '429 + an express species disclosure ('X'-category publications). The family ISR designated WO 2009/128917 A2 (2009-10-22) and US 2010/0143457 A1 (2010-06-10) as category "X" — single-document, anticipatory-style art — against broad family claims. If either expressly recites a substitution at position 313 (or at a position aligning to it), the analysis shifts from §103 to §102 anticipation of claim 1, and §103 becomes moot. These two publications are, in my assessment, the highest-leverage unmined references in this record; the §103 case as pleaded is weaker than the §102 case that may exist but has not been charted. Both were cited in the family's own ISR, which means they may be on or near the '692 file wrapper.

Combination D — "routine alignment" alone (KSR "obvious to try"). A purely KSR-flavored argument — that aligning known hyaluronidase homologs and substituting the most prevalent residue at any position is routine optimization. This is the weakest formulation and directly collides with In re Stepan and Medichem ("general guidance" does not supply a reasonable expectation of success). Halozyme has already pre-empted it: "[n]othing in Dr. Park's results provides a reason to elevate L324 above the hundreds, if not thousands, of other substitutions he predicts would have been tolerated."

Combination E — the '429 alone. Insufficient. The '429 discloses PH20₁₋₄₄₇ and a genus of non-essential-region substitutions but does not identify any non-essential residue, and by Halozyme's reading affirmatively teaches that the substitutions are activity-neutral. Without Chao (or Stern/Zhang), position 313 is missing.

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5. The genus/species question — the real vulnerability

Merck's theory requires a further step: that because claim 1 covers M313K PH20₁₋₄₄₇, and that single species is obvious, the entire genus claim fails. That proposition is legally contested — a claim is judged as a whole, and the Federal Circuit's treatment of broad genus claims against single-species showings is not a simple one-way ratchet. I am not going to assert a controlling authority for it that I have not verified from this record, and I note that the Board never had to reach it in PGR2025-00017 because it rejected the predicate (that the species itself was obvious).

Practically, though, this is where §103 and §112 converge. The same breadth that makes claim 1 enormous (10⁴⁹–10¹¹³ members) is what defeated the claims under §112 in five sibling FWDs. A defendant should not build its case on the §103 ground alone: in this family, §103 has lost and §112 has won.

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6. Dependent claims 2, 5, 7–33

I do not have verbatim '692 dependent-claim text; the following draws on the parallel '520/'773/‘618 petitions, where the same claim architecture recurs, and must be verified.

• Claim 2 (≥95% identity vs. 91%) — narrower identity floor; obviousness follows a fortiori if claim 1 is obvious, but also narrows the genus and therefore narrows the §112 attack. Note the inverse relationship: the dependent claims are easier to invalidate under §103 (closer to the single-species showing) and harder under §112.
• Claims 7+ (solubility/activity/glycosylation/CHO production) — the '429 itself teaches recombinant production of PH20₁₋₄₄₇ in CHO cells yielding a 447-residue, ~61 kDa glycoprotein with 6 N-linked glycosylation sites (Frost), and teaches "N- and O-linked glycans are attached to polypeptides through asparagine-N-acetyl-D-glucosamine linkages." A dependant requiring CHO expression with N-linked glycans is therefore squarely obvious over the '429 alone. Note that Halozyme has been disclaiming precisely these claims — Merck's '773 filing states Halozyme "has disclaimed an additional 20 claims across 9 patents requiring solubility or increased activity," and argues it is a pattern of retreat from exactly the claims its §112 theory hits.
• Nucleic acid / vector / host cell claims — the '429 teaches preparing a nucleic acid encoding PH20₁₋₄₄₇, inserting it in a plasmid, and transfecting CHO cells; Arming and Zhang both reported recombinant single-substitution soluble PH20. Obviousness of these dependents is comparatively strong.
• Pharmaceutical composition / administration / treatment claims — the '429 claims compositions comprising soluble neutral PH20 polypeptides alone or with therapeutic agents including antibodies and small molecules, and describes subcutaneous administration. Composition and method claims keyed to an obvious polypeptide are obvious on the same record.

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7. Objective indicia (§103 secondary considerations)

Halozyme has indicia available, but nexus is the problem:

• Unexpected results — stability in phenolic preservatives. The specification's data (increased activity retained for ≥4 hours in phenol/m-cresol; the F204P example) is the strongest objective-indicia story. But claim 1 recites no stability element, so this evidence is not commensurate with the claim as issued unless a dependent claim (e.g., a preservative-stability or preservative-containing-composition claim) captures it. This is the classic In re Kao/In re Hiniker nexus failure.
• Long-felt need / failure of others. Halozyme has consistently argued the art taught that even conservative mutations sharply reduce activity (Arming) and that no one had solved stable, multiply-modified PH20s — but again, that speaks to stability/activity genus members, not to a bare position-313 structural claim.
• Commercial success / licensing. ENHANZE® licensing revenue is large, but Merck's point is well taken: the asserted MDASE-family claims do not read on unmodified rHuPH20 (Hylenex), and Halozyme's own Q1 2025 earnings call stated the PGR outcomes would have "absolutely no impact on our ENHANZE business," with MDASE described as "a separate and distinct set of patents." That statement is a self-inflicted nexus problem — it severs the asserted claims from the commercial success Halozyme would otherwise rely on.
• Skepticism / teaching away. Halozyme's best doctrine argument is that the '429's statement that non-essential-region substitutions are activity-neutral is a teaching away from making them. This is genuinely arguable and is the argument that carried the day in PGR2025-00017.

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8. Assessment

Bottom line: the §103 ground as pleaded — '429 + Chao, targeting M313K PH20₁₋₄₄₇ — is a plausible but currently weak-to-moderate case, and the Board has already rejected a materially identical version of it in the sibling FWD (PGR2025-00017). The '692 patent's real exposure is §112, not §103.

The three rules of the analysis:

1. The combination is well-formed but the motivation is thin. The '429 supplies the scaffold and the class of modification; Chao supplies the map. But the '429's own characterization of those substitutions as activity-neutral undercuts the "reason to modify," and the '429 names no non-essential residue. Belden, Metalcraft, In re Stepan, and Medichem all put real weight on the patentee's side of that gap.
2. Residue-prevalence evidence is necessary but not sufficient. "K is the most prevalent amino acid at position 313" makes M313K an available choice; it does not, without more, make it the choice a POSITA would have made, particularly when the '429's teaching is about conservative substitutions and M→K is not conservative.
3. The unmined §102/§103 path is better than the pleaded one. WO 2009/128917 A2 and US 2010/0143457 A1 — the two "X"-category references in the family ISR — are the references most likely to close the "position 313" gap directly, converting this from a §103 case into a §102 anticipation case. Any challenger should chart them first.

Practical posture for a defendant (as of the current record): the claims most likely to fall are the §112 ones, and the FWD is due on or about 2026-10-10; the pragmatic strategy is to let the §112 holding do the work, preserve the §103 and §102 theories as insurance in district court (where §325(d) is unavailable to Halozyme), and not to over-invest in the '429 + Chao framing that the Board has already declined to credit.

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9. Verification gaps and caveats

1. §103 institution status in PGR2025-00046 is not conclusively confirmed. The Institution Decision contains a merits section addressing Ground 3, but I could not read the concluding order/table. Confirm against the decision's disposition before citing.
2. No verbatim dependent-claim text for the '692. Analysis in §6 is drawn from sibling patents with the same architecture.
3. The '692 front-page "References Cited" list remains unretrieved (carried forward from the Prior Art section). If WO 2009/128917 or US 2010/0143457 appear there, Combination C's §325(d) posture changes materially.
4. I have not verified a controlling authority for the "single obvious species invalidates the genus claim" proposition and deliberately do not assert one.
5. Date inconsistency persists. The system date is 2026-09-28 while this task states April 26, 2026; the retrieved record includes September 2026 materials (the PGR2025-00017 FWD reported 2026-09-02). I report the later materials rather than suppress them.
6. No FWD has issued in PGR2025-00046 as of the last retrieved material, and no Federal Circuit appeal exists (no appealable decision). The Google Patents "expires 2034-11-28" adjusted-expiration figure is an estimate, not a legal conclusion.

Primary sources relied on: PGR2025-00046 Institution Decision · PGR2025-00046 Petition (as Ex. 2060 in PGR2025-00039) · PGR2025-00046 POPR (discretionary denial brief) · PGR2025-00017 Final Written Decision · PGR2025-00024 Institution Decision · Acting Director's Decision Referring Petitions to the Board · MSD v. Halozyme IPR/PGR petitions compilation