US 12037618

Patent Overview — US12037618B2

Title: PH20 polypeptide variants, formulations and uses thereof
Patent number: US12037618B2
Application number: US17/327,586
Filed: 2021-05-21
Granted / published: 2024-07-16
Priority date (as listed, an assumption per the source): 2011-12-30
Adjusted expiration (as listed): 2034-07-20
Status: Active
Inventors: Ge Wei; H. Michael Shepard; Qiping Zhao; Robert James Connor
Current assignees (listed): Halozyme Inc; Halozyme Therapeutics Inc
Original assignee: Halozyme Inc

Purpose and plain-language scope (based only on the supplied text):
The patent concerns variants of PH20, an enzyme classified as a hyaluronoglucosaminidase (hyaluronidase, EC 3.2.1.35) — an enzyme that breaks down hyaluronic acid. The classification data place the subject matter in enzyme/hydrolase categories (C12N9/2474) and in medicinal preparations containing enzymes and peptides (A61K38/47, A61K38/43–46), including injectable compositions (A61K9/0019) and combinations of active ingredients (A61K45/06). Formulation-related classifications concern carriers and non-active ingredients (A61K47/00, A61K47/10). Therapeutic-activity classes point to respiratory (A61P11/00) and ophthalmic (A61P27/02) uses, and insulin/hormone classes appear (A61K38/22, A61K38/28).

Some indexed prior-art keywords indicate the disclosed subject matter involves a "polypeptide," an "agent," and an amino acid "position corresponding" to a reference, with "modified" positions — i.e., the claims appear directed to engineered PH20 polypeptides with amino acid modifications defined by position.

What this excerpt does not establish:
The supplied text contains no claim language, no amino acid sequences, no specific modified positions or activity data, and no examples. It does not establish the full scope of any claim, the specific variants, formulations, or uses recited, or the identity of any prior art. Litigation, ownership transfers, and legal status are noted only as source metadata and are not evaluated here.

Source: https://patents.google.com/patent/[US12037618](/patent/US12037618)/en

I'll research known litigation involving US 12037618, starting with the leads embedded in the patent record itself (a PTAB PGR and a New Jersey district court case) and then broadening out.

Good — I have strong leads. Let me pull the specific case details for the New Jersey district court action and the PTAB proceeding.

Let me confirm the litigation portal entries and check whether the '618 patent is asserted in any case beyond the New Jersey action.

Litigation involving US Patent 12,037,618 (US 12037618 B2)

Bottom line: Yes — US 12,037,618 ("the '618 patent," titled PH20 polypeptide variants, formulations and uses thereof, Halozyme, Inc. as assignee) is subject to two known co-pending proceedings, both involving the same two parties. There is one district court case and one PTAB post-grant review. Both remain pending; neither has produced a substantive outcome. I found no other litigation (no other defendants, no CAFC appeal, no ITC action) involving this specific patent.

1. District Court Litigation

Additional context on the case:

• The complaint asserts 15 Halozyme patents relating to PH20/"MDASE" technology. Halozyme's own PTAB mandatory notice lists the patents at issue in the D.N.J. action as: 11,041,149; 11,066,656; 11,952,600; 12,018,298; 12,037,618; 12,049,652; 12,054,758; 12,091,692; 12,104,185; 12,110,520; 12,152,262; 12,077,791; 12,195,773; and 12,264,345 (plus US 10,865,400 named in the notice).
• The accused product is SC Keytruda® (subcutaneous pembrolizumab), which contains berahyaluronidase alfa — a modified PH20. Halozyme alleges the enzyme "includes the amino acid modifications ... covered by the asserted patents." Halozyme seeks damages and an injunction against manufacture, sale, and import of SC Keytruda.
• Sources: Law.com Radar case card (case 2:25-cv-03179, E.D.N.J., filed Apr. 24, 2025, Judge Esther Salas, plaintiff counsel Walsh Pizzi O'Reilly Falanga, defendant counsel Gibbons and Dechert); Justia docket https://dockets.justia.com/docket/new-jersey/njdce/2:2025cv03179/[566903](/patent/566903).

Caveat on dates: Some secondary summaries (Lexology/Pearce IP) render the filing date as "24 April 2024." The court docket and Law.com Radar both show 2025, so the "2024" rendering appears to be a typographical error in that summary. I flag it rather than silently relying on it.

2. PTAB Post-Grant Review

• The Board's institution decision expressly identifies Halozyme, Inc. v. Merck Sharp & Dohme Corp., 2:25-cv-03179 (D.N.J.) as a related matter in which Patent Owner alleges infringement of the '618 patent.
• Sources: Unified Patents PTAB case list (PGR2025-00042 | 12037618 | filed 2025-04-15 | inst. 2025-11-13 | Pending – Instituted); GreyB/IPVerse case page.

3. Related (but distinct) matter — not litigation over the '618 patent

• Merck has filed PGRs/IPRs against other, related Halozyme PH20 patents (e.g., PGR2025-00003, -00004, -00006, -00009, -00017, -00024, -00030, -00033, -00039, -00046, -00050, -00052, -00053, and IPR2026-00312 against US 10,865,400). These involve different patent numbers and are therefore outside the scope of a "US 12037618" search; I note them only to explain the broader dispute. Per Merck, the accused enzyme is its partner Alteogen's "ALT-B4," which Merck contends is unlike the PH20 mutants claimed in Halozyme's patents.

4. Summary table

No outcome or final decision has issued in either proceeding. No CAFC appeal, ITC investigation, or additional defendant involving the '618 patent was identified.

Confidence / limitations

• High confidence in the two proceedings above; they are corroborated by the patent's own Google Patents litigation record (which lists PTAB case PGR2025-00042 as "Pending – Instituted" and a New Jersey District Court case), by the court docket, by the PTAB institution decision, and by multiple law firm/industry reports.
• Lower confidence in exact procedural dates for the D.N.J. case (e.g., the current scheduling order date), which I derived from secondary docket summaries rather than a direct PACER pull. If you need litigation-grade verification, the authoritative sources are the D.N.J. docket for 2:25-cv-03179 (CM/ECF/PACER) and the PTAB Patent Trial and Appeal Board End-to-End (PTAB E2E) docket for PGR2025-00042.
• I did not find any litigation involving a similarly numbered patent to be reported here; all entries above are tied specifically to US 12,037,618 / US 12037618 B2.

I'll research the PTAB proceedings identified in the structured data block.

Let me dig into the institution decision details, panel, and grounds.

Let me pin down the claim-level institution scope, disclaimer, and current trial status.

PTAB Proceedings on US Patent 12,037,618 B2

Canonical list (from the structured "PTAB proceedings on file" block): one AIA trial — PGR2025-00042, status Pending - Instituted.

⚠️ Data-source caution. The structured block renders Petitioner: "Unified Patents PTAB Data" by Unified Patents is licensed under a Creative Commons Attribution 4.0 International License. That string is Google Patents' data-source attribution, not a party. The actual petitioner in PGR2025-00042 is Merck Sharp & Dohme LLC; the patent owner is Halozyme, Inc. (with Halozyme Therapeutics, Inc. as a real party-in-interest). No proceeding on this patent was filed by Unified Patents.

Proceedings overview

There is exactly one AIA trial proceeding on US 12,037,618: PGR2025-00042, Merck Sharp & Dohme LLC v. Halozyme, Inc. — filed 2025-04-15, instituted 2025-11-13, and as of 2026-09-28 still pending at trial stage with no Final Written Decision and no appeal. Breakdown: 1 active / 0 claims canceled / 0 claims sustained on the merits / 0 settled / 0 institution denials. Bottom line for a defendant: this is not a "hardened" patent and not a "claims already canceled" patent — it is a live patent whose validity is being actively litigated at the PTAB on a § 112 theory that has already killed five of its sibling patents. Any demand letter citing the '618 should be read against a very high probability that its claims will not survive the statutory 1-year FWD deadline.

PGR2025-00042 — Merck Sharp & Dohme LLC v. Halozyme, Inc.

• Type: Post-Grant Review (PGR) — the only AIA type available; the petition was filed inside the 9-month PGR window. (Not an IPR, not a CBM.)
• Filed: 2025-04-15. The '618 patent issued 2024-07-16 from Application 17/327,586 (filed 2021-05-21), so the petition was filed within the 9-month window of 35 U.S.C. § 321(c). Petition (Paper 2).
• Status: "Pending - Instituted" (verbatim from the structured data / Unified Patents PTAB case list; institution date 2025-11-13). Plain English: the Board found the petitioner more likely than not to prevail on at least one challenged claim and put the case on a trial schedule; no final merits ruling yet.
• Judge panel: Docket-listed panel Jeffrey N. Fredman, Susan L. C. Mitchell, Cynthia M. Hardman, and Michael A. Valek (PTAB docket aggregation). Caveat: the institution-decision caption is the authoritative panel record — the docket aggregation lists all judges associated with the case, and I could not verify the exact three-judge institution panel from the public snippets.
• Petition grounds (as summarized in the institution decision):
  • Ground 1 — § 112(a) written description, claims 1, 2, 5, 7–33 (with additional dependent-claim-specific written-description attacks on claims 3–4, 6, 17–24, and 28–40). Petitioner argued the claims cover a genus of roughly 10⁶⁰ to 10¹¹³ multiply-modified PH20 polypeptides while the common disclosure provides only ~5,916 single-substitution examples (≈2,500 "active," ≈3,380 "inactive") plus a prophetic "make-and-test" plan — i.e., a fence around a genus without representative species (Ariad).
  • Ground 2 — § 112(a) enablement, claims 1, 2, 5, 7–33: undue experimentation under In re Wands to identify the "active mutants" within the claimed genus.
  • Ground 3 (and further grounds) — § 103 obviousness: at least one obviousness ground built on the '429 patent in combination with Chao (2007 HYAL1 structure work), directed at the I309N substitution in PH20₁₋₄₄₇. (Halozyme's preliminary-response arguments in the record attack this ground as relying on ~30–50 undeclared method steps and unspecified motivation.)
  • Priority/PGR-eligibility: Petitioner also argued the '618 claims get no benefit of the earlier '731 application because that disclosure neither describes nor enables them; because the priority analysis overlaps with Ground 1, the Board addressed eligibility and written description together.
  • Petitioner relied on the Declarations of Michael Hecht, Ph.D. and Sheldon Park, Ph.D.; Patent Owner relied on a Declaration of Barbara Triggs-Raine, Ph.D.
• Institution decision: Instituted 2025-11-13, and the decision states: "we determine that the information presented shows that it is more likely than not that Petitioner would prevail in establishing unpatentability of claims 3, 4, 6, and 34-40 of the '618 patent, and therefore, we grant post-grant review." The Board also confirmed the '618 patent is PGR-eligible. Read literally, that is a partial institution limited to claims 3, 4, 6, and 34–40; the broadly-drafted independent claims identified in Grounds 1–2 (claims 1, 2, 5, 7–33) were not included in the institution grant. I flag this as the single most important item for a defendant to confirm on PTAB E2E, because of the disclaimer question below.
• Pre-institution discretionary denial: Halozyme filed a Fintiv-style request for discretionary denial (Paper 14); Merck opposed (Paper 18; opposition brief dated 2025-07-17). In August–September 2025, the Director (Coke Morgan Stewart, Acting Under Secretary and Director) denied discretionary denial and referred the petition to the Board, incorporating the reasoning from Merck Sharp & Dohme LLC v. Halozyme Inc., PGR2025-00006, Paper 29 (2025-06-12). Key reasoning: the Board's FWD "will issue nearly four years before the district court trial occurs" (D.N.J. trial projected ~May 2030), so there is no duplication/conflict risk; the Director also noted that "all patents in the district court litigation … contain the same § 112 flaws." The Director's order expressly barred rehearing/Director Review requests until the Board ruled on institution.
• Final Written Decision: None as of 2026-09-28. Statutory deadline under 35 U.S.C. § 326(a)(11) is one year from institution, i.e. on or about 2026-11-13 (extendable up to six months for good cause, to ~2027-05-13). Peer-track FWDs on sibling patents have landed at the deadline. No claim of the '618 patent has been held unpatentable, and no claim has been sustained on the merits.
• Statutory disclaimer / claim disposition (⚠️ verify): public record snippets from the institution decision include the sentence "Neither Patent Owner's disclaimer of claims 3, 4, 6, and 34-40 nor the additional limitations required by dependent claim 17 and 18 impacts the claim differentiation argument." That indicates Halozyme statutorily disclaimed those claims, and I could not reconcile from public sources whether the disclaimer predated or postdated institution — the two data points are in tension if the instituted claims were 3, 4, 6, and 34–40. What is not in doubt is the factual pattern in the sibling cases in this campaign: Halozyme disclaimed claims before institution in the '520, '652, and '185 PGRs (per Venable's report), and Merck characterized Halozyme's approach as "disclaiming (rather than defending) many of the claims Merck has challenged." Check the 37 C.F.R. § 1.321(a) disclaimer documents and the Board's institution papers on PTAB E2E before relying on any particular claim being alive or dead.
• Settlement / termination: None. No termination, no adverse judgment, no settlement on the docket. This is a contested, instituted trial.
• Appeal: None. No FWD → nothing appealable; no Federal Circuit docket exists for this proceeding. Note that Halozyme did appeal (or is positioned to appeal) the sibling FWDs — commentary in the Korean trade press flags possible CAFC appeals on the '600/'262 decisions, but no CAFC appeal of this proceeding exists.
• Notable in-trial motion practice: Halozyme pursued additional discovery on real parties-in-interest, seeking to establish that Merck & Co., Inc. (MCI) — not just MSD LLC — is an unnamed RPI. Petitioner produced documents in December 2025 (EX2402–EX2444 range, including outside-counsel engagement letters and expert retainer letters), and the parties exchanged redaction disputes through 2026-01/02. This matters: if MCI is held to be an RPI/privy, it expands the reach of PGR estoppel and affects who is bound by the outcome. No public decision on the RPI motion surfaced in my searches.
• Litigation counterparty: Halozyme, Inc. v. Merck Sharp & Dohme Corp., No. 2:25-cv-03179 (D.N.J.), filed 2025-04-24, asserting 15 Halozyme MDASE-family patents (including the '618) against Keytruda Qlex™ (pembrolizumab + berahyaluronidase alfa-pmph).
• Defensive value: The '618 patent is currently fully enforceable — no claim has been canceled, so an infringement theory built on it is not sanction-bait. But the risk allocation strongly favors a defendant: the Board already found a § 112 case "more likely than not" on a subset of claims, the Director refused to discretionarily deny, and the identical written-description/enablement theory has now invalidated five sibling Halozyme patents (see below). A defendant in the D.N.J. case should be building its non-infringement and § 112(a)/(b) case now, not waiting for the FWD.

Strategic summary

Claim status of US 12,037,618 — CANCELED vs. SUSTAINED vs. UNTESTED.
Nothing on this patent has been canceled by the Board. No claim is CANCELED (no FWD) and no claim is SUSTAINED (no FWD). The claims are best described as TESTED-but-UNDECIDED: claims 3, 4, 6, and 34–40 are within the instituted trial scope (with a probable, but unconfirmed, statutory disclaimer of those same claims), while the remaining challenged claims identified in Grounds 1–2 (1, 2, 5, 7–33) appear not to have been instituted and therefore fall outside the trial — but also outside any estoppel. Do not tell a court that any claim of the '618 has been invalidated. Contrast this with the sibling patents, where claims are dead: US 11,952,600 (claims 1–4, 8–21 unpatentable, 2026-05-12), US 12,152,262 (claims 1–4, 8–13, 2026-05-18), US 12,018,298 (2026-06-08), US 12,123,035 (2026-06-24), and US 12,110,520 (2026-09-01) — each invalidated on the same § 112(a) written-description/enablement rationale (claims covering ~10⁶⁰–10⁶³ polypeptide genera, insufficient representative species, no reliable prediction beyond 2–3 (or ~5) concurrent substitutions), while the Board rejected the obviousness grounds in the FWDs. The '618 is next in that queue (FWD due ~2026-11-13).

Estoppel landscape. Because no FWD has issued yet, no estoppel has attached under 35 U.S.C. § 325(e)(2) (PGR counterpart to IPR's § 315(e)(2)). Once the '618 FWD issues, Merck and its privies will be barred in the D.N.J. action from asserting any ground they raised or reasonably could have raised in the instituted trial — but only as to the claims for which the FWD issues; under Shaw Industries v. Automated Creel Systems, claims that were challenged but not instituted generate no estoppel. Two practical consequences for other defendants: (1) you are not estopped — a new defendant (not in privity with Merck) can file its own challenge, but the PGR window closed 2025-04-16, so only IPR under §§ 102/103 on patents/printed publications (§ 311(b)) is available; the winning § 112 theory can only be run in district court. (2) Halozyme's RPI motion matters to you — if Merck & Co., Inc. is held to be a privy, the estoppel net widens, but MSD's 14 PGRs/3 IPRs on the other MDASE patents do nothing to estop or bind challenges to the '618.

Pattern signals. This is a coordinated campaign, not a one-off. Since November 2024, Merck has filed 14 PGRs and (in March 2026) 3 IPRs against the Halozyme MDASE/PH20 family; 13 of 14 PGRs were instituted (the 14th, PGR2025-00087 on US 12,371,685, was denied institution by Director order on 2026-05-15). The '618 is one of the small number of asserted patents still standing, and the FWD record so far is 5-for-5 against Halozyme on § 112, 0-for-5 on Merck's obviousness grounds. The patent owner has been aggressive on the procedural front — Fintiv discretionary-denial requests in every case (denied), pre-institution statutory disclaimers of the choicest attacked claims, and an RPI/privilege discovery fight — which is itself a signal of weakness on the merits. No defensive aggregator is in the chain; the only "Unified Patents" reference is the Google Patents data attribution. No settlement has been reported, and Halozyme's parallel offensive (its IPR against Alteogen's PH20 manufacturing patent) was denied institution on 2026-05-15, further tilting the position toward the defendants.

Recommended next steps

If you are a defendant facing assertion of the '618:

1. Do not treat the '618 as settled law. Pull the institution decision itself (Banner Witcoff mirror: https://bannerwitcoff.com/wp-content/uploads/2025/11/PGR2025-00042.pdf; official copy on PTAB E2E at https://ptacts.uspto.gov/ptacts/public-informations/petitions/[1557626](/patent/1557626)/) and read § IX (written description) and § X (enablement) verbatim — those sections, plus the parallel reasoning in the '600 and '262 FWDs, are your § 112 roadmap. Verify (a) the exact instituted claim set, (b) the panel caption, and (c) whether Halozyme's disclaimer of claims 3, 4, 6 and 34–40 was filed before or after 2025-11-13.
2. Ride the FWD, don't race it. The statutory FWD deadline is ~2026-11-13 (35 U.S.C. § 326(a)(11); extendable to ~2027-05-13 for good cause). Any stay motion in D.N.J. should quote the Director's own reasoning from the referral decision: the Board's FWD "will issue nearly four years before the district court trial occurs" (projected May 2030), and "all patents in the district court litigation … contain the same § 112 flaws."
3. Preserve your own record. Because the '618 PGR window is closed and you are not a privy of Merck, your independent validity challenge is limited to IPR on § 102/§ 103 art; keep § 112(a)/(b) alive as a district-court defense (no PTAB route to it now). Confirm whether you are potentially in privity with MSD before assuming you are free to re-litigate the same art.
4. Track the RPI motion. Whatever the Board decides about Merck & Co., Inc. as an unnamed RPI will be used to define the estoppel boundary post-FWD — worth monitoring on the docket (PTAB E2E; case page https://ipverse.greyb.com/ptab-web/cases/case-details/PGR2025-00042; aggregator https://portal.unifiedpatents.com/ptab/case/PGR2025-00042).
5. Watch for a CAFC appeal. Halozyme has signaled it will contest the adverse sibling FWDs; an appeal of the '618 FWD (should one issue) would follow the same § 112 written-description/enablement script and is the last realistic path to revival. No appeal exists today.
6. Litigation context for the demand letter: the co-pending case is Halozyme, Inc. v. Merck Sharp & Dohme Corp., 2:25-cv-03179 (D.N.J.) (https://portal.unifiedpatents.com/litigation/New%20Jersey%20District%20Court/case/2%3A25-cv-03179), asserting 15 MDASE patents.

If you are evaluating the patent portfolio as a whole: the operative takeaway is that the '618 is next in a line of Halozyme PH20 patents being invalidated for claiming an enormous genus of multiply-modified PH20 polypeptides without a representative or enabling disclosure. Plan around a 2026-11-13 FWD.

Confidence / gaps I could not close: (i) the exact institution date is confirmed 2025-11-13; (ii) the institution claim scope is quoted directly but is in apparent tension with the disclaimer snippet — verify on E2E; (iii) the exact three-judge institution panel and the Patent Owner Response filing date (~2026-01-15 per docket aggregation) are worth confirming against the docket; (iv) no FWD, settlement, or appeal exists on this patent as of 2026-09-28. I did not invent any proceeding number — the only AIA trial on US 12,037,618 is PGR2025-00042.

I'll research the assignment record and litigation history for US 12037618 before assembling the report.

Let me verify the assignment records and Halozyme's corporate status.

Let me attempt to confirm the specific reel/frame records and inventor affiliations.

Ownership & Assignment Analysis — US 12,037,618 B2

Patent: US 12,037,618 B2 — "PH20 polypeptide variants, formulations and uses thereof"
Application: 17/327,586, filed 2021-05-21; granted 2024-07-16; adjusted expiration 2034-07-20
Current assignee of record: Halozyme, Inc. (San Diego, CA), a wholly owned subsidiary of Halozyme Therapeutics, Inc. (NASDAQ: HALO)

Sourcing note / verification limit. I reconstructed this from the patent's Google Patents legal-events record, the USPTO PTAB record, the E.D.N.J. docket, and Halozyme's FY2024 Form 10-K. The assignment entries below are real and are drawn from the Google Patents legal-events list (which mirrors Assignment Center records), but I could not execute a live query against Assignment Center in this session, so I can only confirm one reel/frame value — 056331/0368 — because the corrective-assignment entry itself cites it. I have deliberately left the other reel/frame fields marked as unverified rather than inventing numbers. Correspondent-of-record data (the attorney who filed each recording) is not available from the sources I could reach and is marked accordingly.

Inventors

Pattern notes:

• Geographic clustering is consistent with a single employer. Three of four inventors list San Diego–area residences within ~40 miles of Halozyme's San Diego headquarters; Shepard (the company's scientific founder) is listed in Eugene, Oregon.
• Split assignment structure is the one genuinely unusual feature. Shepard assigned his rights directly to Halozyme, Inc., while Wei, Zhao and Connor assigned to Halozyme Therapeutics, Inc. (the parent), which then transferred to Halozyme, Inc. Two different assignee entities for four co-inventors on the same application suggests differing employment/consulting relationships or differing invention-assignment agreements — a documentation quirk, not an ownership red flag, since both entities are in the same corporate family.
• Departure pattern: unclear / not determinable. I could not find evidence of inventors departing within 12 months of filing. Note that the operative filing here is a 2021 continuation of a 2011-priority application, so a "departure within 12 months of filing" test is of limited diagnostic value on its face.

Original assignee

Halozyme, Inc. (San Diego, CA) is the entity named on the issued patent, per the USPTO issue announcement. Halozyme, Inc. is a wholly owned subsidiary of Halozyme Therapeutics, Inc. — the 10-K expressly states: "References to 'Halozyme,' 'the Company,' 'we,' 'our,' 'ours,' and 'us' refer to Halozyme Therapeutics, Inc., its wholly owned subsidiaries, Halozyme, Inc., Antares Pharma Inc., and Antares Pharma Inc.'s wholly-owned subsidiaries…"

• Primary line of business: biopharmaceutical drug-delivery company. Commercializes the ENHANZE® platform built on rHuPH20, a recombinant human PH20 hyaluronidase, and licenses it to Roche, Takeda, Pfizer, Janssen, AbbVie, Eli Lilly, BMS, argenx, ViiV, and others.
• Does it ship a product embodying the claims? Yes. Halozyme sells bulk rHuPH20 and its own PH20-containing proprietary product Hylenex® (recombinant human hyaluronidase), plus XYOSTED® devices. FY2024 product sales were ~$166.6M proprietary / $86.3M bulk rHuPH20. The claims at issue recite modified PH20 variants (the "MDASE" portfolio); Halozyme's own enzyme products and its partners' co-formulations are the commercial embodiments of this family.
• Current status: operating and highly profitable. FY2024 total revenue $1.015 billion (first billion-dollar year), net income $444.1M. No bankruptcy, no dissolution, no acquisition of the company.

Assignment timeline

All four recordings below occurred within three days of each other and predate issuance by ~3 years. Every one is intra-corporate.

• 2021-05-24 (executed) / recorded 2021-05-24 — Reel unverified

  • Conveyance: Assignment
  • Assignor: SHEPARD, H. MICHAEL (individual)
  • Assignee: HALOZYME, INC.
  • Correspondent: not available from reachable sources — could not verify
  • Context: inventor-to-company assignment of rights; distinguished from the other three inventors by naming the subsidiary rather than the parent.

• 2021-05-24 (executed) / recorded 2021-05-24 — Reel 056331/0368 (confirmed via the corrective entry, which cites the original recording)

  • Conveyance: Assignment
  • Assignor: CONNOR, ROBERT JAMES; WEI, GE; ZHAO, QIPING (individuals)
  • Assignee: HALOZYME THERAPEUTICS, INC.
  • Correspondent: not available from reachable sources — could not verify. No recurrence can be assessed on a single data point.
  • Context: inventor-to-company assignment to the parent entity.

• 2021-05-24 (executed) / recorded 2021-05-24 — Reel unverified

  • Conveyance: Assignment
  • Assignor: HALOZYME THERAPEUTICS, INC.
  • Assignee: HALOZYME, INC.
  • Correspondent: not available from reachable sources — could not verify
  • Context: internal reorg / intra-group consolidation — transfer from parent to its wholly owned subsidiary; no change in ultimate beneficial ownership.

• 2021-05-26 (executed) / recorded 2021-05-26 — Reel unverified (corrects Reel 056331/0368)

  • Conveyance: Correction (corrective assignment)
  • Assignor: CONNOR, ROBERT JAMES; WEI, GE; ZHAO, QIPING
  • Assignee: HALOZYME THERAPEUTICS, INC.
  • Correspondent: not available from reachable sources — could not verify
  • Context: administrative correction only — stated purpose is "to correct the docket number previously recorded at Reel 056331, Frame 0368." No substantive ownership change.

No post-issuance assignment exists. The chain terminates at Halozyme, Inc. There has been no transfer to a licensing vehicle, no securitization, no sale, and no defensive-aggregator acquisition.

Timeline diagram

timeline
    title Ownership of US 12037618
    2011 : Priority application filed by Halozyme
    2021 : Continuation filed 21 May 2021
         : Shepard assigns rights to Halozyme Inc
         : Wei Zhao Connor assign to Halozyme Therapeutics
         : Halozyme Therapeutics transfers to Halozyme Inc
         : Corrective assignment recorded 26 May
    2024 : Patent US 12037618 B2 granted
    2025 : Halozyme sues Merck in New Jersey
         : Merck files PGR2025-00042

NPE / troll-pattern signals

1. Shell-entity transfer — not present. The only inter-entity movement is Halozyme Therapeutics, Inc. → Halozyme, Inc. Both are identified in Halozyme's FY2024 Form 10-K as parent and wholly owned subsidiary of the same NASDAQ-listed company. Neither carries an "IP / Patents / Licensing / Holdings / Ventures" suffix, neither is a single-purpose LLC, and the ultimate owner reports $1.015B in revenue and ships product. Recurrence in the chain is parent→sub, not operating-company→shell.

2. Known asserter in the chain — not present. No assignee matches any public NPE list (Acacia, Marathon, IV, IPNav, Wi-LAN, Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, DGC, Spangenberg entities). The owner is Halozyme, Inc. Unified Patents' own PTAB portal classifies the Owner as "Halozyme Inc — Operating Company" for PGR2025-00042. Critically, the Google Patents page's line "Petitioner: 'Unified Patents PTAB Data' by Unified Patents is licensed under a Creative Commons Attribution 4.0 International License" is a data-licensing attribution for Google's PTAB dataset — not a statement that Unified Patents filed the PGR. The actual petitioner is Merck Sharp & Dohme LLC, a "Large Operating Company," unverified as such in the portal but named in the petition caption and the litigation record. Do not read this field as an NPE signal.

3. Repeat correspondent across the chain — unclear. I could not retrieve the attorney of record on the recordings. There are four recordings in a 72-hour window, which is textbook batch filing by a single prosecution firm, but that in itself says nothing adverse. A single appearance is expressly not a finding under the stated test, and I have zero appearances to count, so this is unclear, not adverse.

4. Cascading transfers — not present. Two substantive transfers, both intra-group, all executed/recorded 2021-05-24, i.e., a single-day cluster, not a cascade of chained LLCs across <24 months. No shared registered-agent service address, no common-principal pattern, no interposition of intermediaries.

5. Pre-litigation transfer — not present (inverse pattern). All assignments are dated 2021-05-24, roughly 47 months before the first infringement suit (2025-04-24). There is no assignment within 6 months of filing. The chain was not arranged to enable assertion; Halozyme held the patent for four years, offered a license in March 2025, and sued when negotiations failed.

6. Bankruptcy fire-sale — not present. Halozyme Therapeutics has not filed Chapter 7 or 11. FY2024 net income was $444.1M and cash plus marketable securities were $596.1M. No record of any proceeding.

7. Privateering — not present. Halozyme is the named plaintiff itself in Halozyme, Inc. v. Merck Sharp & Dohme Corp., Civil Action No. 2:25-cv-03179-ES (D.N.J., filed 2025-04-24, Judge Esther Salas), asserting 15 Halozyme-owned patents including US 12,037,618 against Merck's SC KEYTRUDA® / berahyaluronidase alfa. There is no NPE intermediary asserting on Halozyme's behalf and no indication of a transfer to one. Merck counter-asserted nothing — it filed PGRs instead (PGR2025-00042, filed 2025-04-15, instituted 2025-11-13). The closest thing to a "privateering" look is that Halozyme's revenue model is royalty/licensing-heavy, but it sues from its own balance sheet against a direct competitor in the same SC-delivery market.

8. Defensive aggregator — not present. The chain does not terminate at RPX, AST, LOT Network, Unified Patents, or OIN. The patent remains with Halozyme and is actively asserted.

Verdict

Operating-company assertion.

The assignment chain contains exactly three substantive recordings and one correction, all executed and recorded between 2021-05-24 and 2021-05-26, all internal to the Halozyme corporate family (Reel 056331/0368 is the sole confirmed reel/frame; Halozyme Therapeutics, Inc. → Halozyme, Inc. is parent-to-wholly-owned-subsidiary per the FY2024 Form 10-K). The patent has never left the operating company: Halozyme, Inc. is the assignee of record and the named plaintiff in D.N.J. 2:25-cv-03179-ES filed 2025-04-24, asserting this patent against Merck's SC KEYTRUDA® — roughly 47 months after the last assignment, which negates any pre-litigation-transfer inference. Halozyme is a $1.0B-revenue NASDAQ operating company that manufactures rHuPH20 and sells Hylenex®, and it is suing a competitor (Merck), not a downstream licensee or an unrelated industry participant. Not a single NPE signal is present; the only "unclear" call is the repeat-correspondent test, which fails for lack of retrievable correspondent data rather than for evidence of a pattern.

Verify at: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (search patent number 12037618); mirror index at https://assignment.uspto.gov/patent/index.html · Google Patents legal events — https://patents.google.com/patent/[US12037618B2](/patent/US12037618B2)/en · PGR2025-00042 — https://portal.unifiedpatents.com/ptab/case/PGR2025-00042

Caveat: reel/frame values other than 056331/0368 and all correspondent-of-record fields should be confirmed directly in Assignment Center before being relied on, as noted at the top of this report.

I'll research US 12037618 and its cited prior art. Let me start with several targeted searches.

Good leads. Let me dig into the specific "References Cited" section for this patent.

Let me find the PTAB proceeding for this specific patent and its identified prior art.

Bottom line up front

I could not retrieve the verbatim "(56) References Cited" block from the front page of US 12,037,618 B2 itself (Google Patents' machine-readable copy of this document, which is what I was given as the authoritative text, does not include the front-page reference list). What I can establish, from the related family member's published front page and from the co-pending PTAB record, is the following. I flag confidence levels explicitly rather than smoothing over gaps.

1. The patent, identified literally

Source: https://patents.google.com/patent/US12037618/en ; https://portal.unifiedpatents.com/patents/patent/US-[12037618](/patent/12037618)-B2 ; https://ipverse.greyb.com/ptab-web/cases/case-details/PGR2025-00042

Note on statutory framework: because MSD filed post-grant review (not IPR) against this patent, the Office is treating US 12,037,618 as AIA (first-inventor-to-file) subject matter notwithstanding the 2011 priority claim. That matters for which § 102 subsections apply. I have not independently verified the AIA/pre-AIA determination from the file wrapper.

2. References appearing on the family's cited-reference list

The FreePatentsOnline front page for the directly related Halozyme publication US 2025/0154488 A1 (same title, same family) lists the following under "US Patent References" and "Other References" — this is the closest proxy I could obtain to the '618's own (56) block, and it is very likely identical in substance:

U.S. Patent References

• US 12,077,791 B2 (2024-09-03) — Halozyme family member, "PH20 polypeptide variants with a modification at position 309…"
• US 12,037,618 B2 (2024-07-16) — the patent at issue itself
• US 11,066,656 B2 (2021-07-20) — Halozyme family member
• US 10,865,400 B2 (2020-12-15) — Halozyme family member, "PH20 polypeptide variants, formulations and uses thereof"
• US 9,447,401 B2 (2016-09-20) — Halozyme family member (this is the patent that issued from the '731 Application, the parent line)
• US 7,767,429 B2 (2010-08-03) — Bookbinder et al., "Soluble hyaluronidase glycoprotein (sHASEGP), process for preparing the same, uses and pharmaceutical compositions comprising thereof"

Other References

• Chao, K.L., Muthukumar, L., Herzberg, O. "Structure of human hyaluronidase-1, a hyaluronidase involved in tumor progression," Biochemistry 2007; 46(23):6911–6920.

Source: https://www.freepatentsonline.com/y2025/0154488.html

Additional art listed against US 12,037,618 on Unified Patents' "Patent Art (179)" panel (lower confidence — I could not confirm whether these are examiner citations or IDS submissions):

• US 6,437,025 B1 (Nektar Therapeutics) — poly(ethylene glycol) derivatives with proximal reactive groups
• US 5,672,662 A — PEG/related polymers monosubstituted with propionic/butanoic acids
• US 2010/0074885 A1 (Takeda) — combinations and methods for subcutaneous administration of immune globulin and hyaluronidase
• US 2009/0253175 A1 — "Soluble hyaluronidase glycoprotein (sHASEGP), process for preparing the same, uses and pharmaceutical compositions comprising thereof"
• US 8,202,517 B2
• WO 2004/056312 A2

Source: https://portal.unifiedpatents.com/patents/patent/US-12037618-B2

3. Reference-by-reference § 102 analysis

3.1 US 7,767,429 B2 — Bookbinder et al. (Halozyme)

• Citation: US 7,767,429 B2, "Soluble hyaluronidase glycoprotein (sHASEGP), process for preparing the same, uses and pharmaceutical compositions comprising thereof." Filed 2004-03-05 (per PTAB record; some sources say originally filed 2003). Issued 2010-08-03.
• Description: Discloses soluble, neutral-active hyaluronidase glycoproteins ("sHASEGPs"), including human soluble PH-20; teaches substantially purified glycoproteins with ≥95% identity to sHASEGP; claims a specific truncated version composed of positions 36–482 of SEQ ID NO:1; states that "single amino acid substitutions in non-essential regions of a polypeptide do not substantially alter biological activity."
• § 102 potential: This is the reference the PTAB petitions actually rely on — but as § 103 art (obviousness), typically combined with Chao and POSA knowledge, not as a § 102 anticipation. Nothing in the cited passages discloses a PH20 polypeptide with a modification at the position corresponding to 309 of SEQ ID NO:3, so it does not appear to anticipate claim 1 or its dependents on its own. Two additional § 102 caveats worth raising: (i) it is commonly owned by the same assignee (Halozyme), which may remove it as prior art under AIA § 102(b)(2)(C) if the '618 is AIA-governed; (ii) named inventorship overlap should be checked against the § 102(b)(1)(A)/(b)(2)(C) exceptions.
• Sources: PTAB institution decisions at https://biologicshq.com/wp-content/uploads/2025/10/PTAB-PGR2025-00052-Institution-Decision.pdf and https://biologicshq.com/wp-content/uploads/2025/10/PTAB-PGR2025-00046-Institution-Decision.pdf

3.2 Chao et al. 2007, Biochemistry 46:6911–6920

• Citation: Chao KL, Muthukumar L, Herzberg O, Biochemistry 2007; 46(23):6911–6920. Published 2007 (well before the 2011 priority date).
• Description: Reports the crystal structure of human HYAL1; uses a structure-based alignment of the five human hyaluronidases (hHyal-1 to -4 and PH-20); identifies the Hyal-EGF domain and conserved/invariant catalytic residues; notes human hyaluronidases share 33–42% sequence identity with higher active-site conservation.
• § 102 potential: A printed publication describing protein structure and conserved residues — it is § 103 art (as petitioner expressly frames it), not an anticipating disclosure of a specific modified PH20 polypeptide. It cannot anticipate claim 1. It is potentially relevant to § 102(a)(1) only to the extent it discloses the unmodified PH20 sequence context.

3.3 US 9,447,401 B2

• Citation: Issued 2016-09-20. Halozyme family member (the '731 Application line). Same title.
• § 102 potential: This is a member of the same family as the '618 (priority 2011-12-30). As commonly owned, same-family subject matter it is not "by another" and/or falls within the § 102(b)(2)(C) common-ownership exception. It should not be relied on as anticipating prior art for the '618. Note also that a patent's own priority chain cannot anticipate it.

3.4 US 10,865,400 B2 (2020-12-15) and US 11,066,656 B2 (2021-07-20)

• Same family, same assignee, same specification. Same § 102 disqualification analysis as 3.3. In petitioner expert testimony (EX1004) these family members are cited as evidence of what the common disclosure contains (e.g., "soluble PH20 polypeptides include any that has the sequence of amino acids set forth in SEQ ID NOS: 3 or 32-66 or a sequence of amino acids that exhibits at least 85% sequence identity"), which is a written-description/enablement argument, not a § 102 anticipation theory.

3.5 US 12,077,791 B2 (2024-09-03)

• Family member with claim scope directed to position 309 modifications (same as '618 claim 1). Same disqualification; also post-dates the '618's priority date.

3.6 PEG / formulation references (US 6,437,025; US 5,672,662; US 2010/0074885; WO 2004/056312)

• These appear in the family's art listing, plausibly as IDS-submitted background art relevant to the PEGylation and formulation claims.
• § 102 potential: PEG-derivative chemistry patents do not disclose the claimed modified PH20 polypeptides and cannot anticipate claim 1. US 2010/0074885 (immune globulin + hyaluronidase subcutaneous combinations) and WO 2004/056312 could bear on the composition/method claims, but only if a given claim's full complement of limitations (including the specific PH20 substitution) is disclosed. On the record available to me, none does.

4. Direct answer on anticipation

No reference I identified appears to be a clean § 102 anticipation of claim 1 of US 12,037,618. Claim 1 requires a modified PH20 polypeptide with a modification at the position corresponding to position 309 of SEQ ID NO:3. The two references that matter on the merits — US 7,767,429 and Chao 2007 — are deployed by petitioners in the parallel PGRs as a § 103 combination ('429 + Chao + POSA knowledge), not as anticipatory art. Every other item on the cited-reference list is either (a) the applicant's own commonly owned family (§ 102(b)(2)(C)-disqualified), or (b) background chemistry/formulation art that does not disclose the 309 modification.

If you need a definitive § 102 mapping, the authoritative document is the PGR2025-00042 petition and institution decision (Merck Sharp & Dohme LLC v. Halozyme, Inc.), which enumerates the challenged claims and the specific grounds. I was not able to pull the PGR2025-00042 petition text itself before exhausting my search budget, so the ground-by-ground mapping above for the '618 specifically is inferred from the closely parallel PGRs (PGR2025-00046, -00052, -00033) against sibling patents sharing the same specification.

Suggested next verification steps: (1) pull the "References Cited" block from the '618's own front page via USPTO Patent Center / Patent Public Search for application 17/327,586; (2) retrieve PGR2025-00042 Petition Paper 2 and Exhibit 1005/1006 to confirm exhibit numbering for this specific patent; (3) confirm the AIA vs. pre-AIA status from the file wrapper, since it changes whether § 102(a)(2)/(b)(2)(C) or pre-AIA § 102(e) governs the family-member citations.

Confidence: high on the patent identity, dates, assignee, claim-1 subject matter, and on the '429/Chao art; medium on the exact composition of the '618's own (56) block (inferred from the sibling publication US 2025/0154488 A1); low on whether the PEG/formulation references listed on Unified Patents are examiner citations or IDS submissions.

I'll ground this analysis in actual prior-art references. Let me search for the relevant material, including the PTAB challenge to this patent.

Key finding: PGR2025-00042 challenges this exact patent (12,037,618 = US12037618). Let me pull the claims and the institution decision grounds.

Let me pin down the specific prior-art references and the actual claim language.

Sourcing note (important)

The page you supplied does not contain a labeled "Prior Art" section. The fetched text of US12037618B2 contains the abstract, the definitions/description, the classification tree, and the legal-events table — but no "Prior Art," "Cited By," or reference-list section, and no claim text. Rather than invent references, I reconstructed the actual prior-art record from the prosecution/PGR record for this exact patent. I have kept all identifiers literal: US 12037618 B2 = application 17/327,586 = "the '618 patent" (i.e., 12,037,618), which is the patent challenged in PGR2025-00042 (Google Patents: "PTAB case PGR2025-00042 filed (Pending - Instituted)"). Where I am relying on a party's characterization rather than the claim text itself, I say so.

1. The claim that has to be met

From the PGR2025-00042 petition and the Board's institution decision:

• Claims 1–40 are directed to modified human PH20 polypeptides that "(i) must have one amino acid substitution at position 309, and (ii) may have between 20 and 41 additional substitutions at any of 430+ positions, and to any of 19 other amino acids" — capturing "between 10⁶⁰ and 10¹¹³ distinct PH20 polypeptides." (Petition, PGR2025-00042, as reproduced in PGR2025-00039 Ex. 2056.)
• The position-309 substitutions recited/embraced include I309N, I309L, I309E, I309G, I309H, I309M, I309Q, I309R, I309S, I309T, I309V (the "Active Mutants," >50% activity).
• Claim 1 also carries: a sequence-identity limitation (expressly recited in the family at "at least 91% sequence identity" to SEQ ID NO:7 or a C-terminal truncated soluble fragment — see US 2013/0302275 A1 claim language), a ≥40% hyaluronidase activity requirement, and provisos excluding A at 200/333/358/393, N at 111/249, Q at 113, G at 176, T at 252.
• Dependent claims add increased stability / increased activity relative to unmodified PH20 (claims 3, 6, 23), and claims 30–40 require use of an "active mutant," including compositions/formulations (Google Patents page; PGR2025-00042 institution decision, https://bannerwitcoff.com/wp-content/uploads/2025/11/PGR2025-00042.pdf).

The critical limitation for §103 is the single required substitution at position 309. Everything else in the claims (loose identity, optional extra substitutions, activity floor) is broad, but the position-309 requirement is the point of novelty that any combination must reach.

Priority effect on the §103 analysis

The petition's premise is that the claims are not entitled to the Dec. 30, 2011 provisionals or the Dec. 28, 2012 '731 application (that is what makes the patent PGR-eligible, i.e., an effective filing date on/after March 16, 2013). The Board instituted a PGR, so it accepted that predicate at the institution stage. This matters in two ways for §103:

1. It does not help patentability: every reference discussed below published before December 2011, so it is prior art under either the pre-AIA or AIA regime.
2. It expands the available art: if priority is broken, the family's own intervening publications and the '731 application can potentially be used, subject to the §102(b)(2)(C) common-ownership exception.

2. The prior art actually in the record

Sources: PGR2025-00042 petition and institution decision (https://bannerwitcoff.com/wp-content/uploads/2025/11/PGR2025-00042.pdf; https://www.docketalarm.com/cases/PTAB/PGR2025-00039/Merck_Sharp_%26_Dohme_LLC_v._Halozyme_Inc/06-16-2025-Patent_Owner/Exhibit-2056-EX2056___PGR2025_00042_Petition.pdf); PGR2025-00003 decision quoting the '429 patent at 16:14–20 (https://www.statnews.com/wp-content/uploads/2025/06/PGR2025-00003-Decision.pdf); Venable summary of the family-wide PGRs (https://biologicshq.com/ptab-grants-institution-of-three-pgrs-related-to-mercks-keytruda-qlex/).

3. The obviousness grounds, and how each fares

Ground A — '429 patent + Chao (+ ordinary skill in rational design)

The Petitioner's theory (this is the strongest, most complete motivation narrative in the record):

• Motivation (teaching of the '429 patent): it expressly directs making a particular kind of change (a single amino-acid substitution), at a particular place (non-essential regions of PH20₁₋₄₄₇), in a particular sequence (PH20₁₋₄₄₇), and states those variants retain activity — i.e., it tells the artisan the effort will succeed and that the resulting enzyme has the same utility/therapeutic applications.
• Mechanism for identifying "non-essential" positions: Chao supplies a HYAL1 crystal structure, an MSA of the five human hyaluronidases, conserved catalytic residues, disulfide cysteines, glycosylation sites, and domain boundaries (Hyal-EGF, 337–409). Combining with the '429 patent yields an identification of the non-conserved positions.
• Expectation of success: the '429 patent's own assurance ("do not substantially alter biological activity") plus its express claims to such variants; the "≥40% activity" floor is satisfied by that assurance.
• Amino-acid choice: the MSA shows which residues occur naturally at the corresponding positions in homologous hyaluronidases, making the choice of the substituent a matter of routine design.

Why it did not carry the day (and this is the analytically decisive part): the Board credited the patent owner on the motivation step. In the institution decision on Ground III the Board stated it "agree[d] with Patent Owner that Petitioner has not provided any persuasive reason to particularly target position 309 of a PH20 polypeptide for modification as required by claim 1," noting that neither the '429 patent nor Chao "specifically identifies or discusses position 309," and that "tolerance is not a positive reason to make a substitution" (PGR2025-00042 institution decision, §XI.C). In other words:

• The '429 patent's guidance is generic ("non-essential regions"), and it does not enumerate which residues those are.
• Chao's MSA/alignment tells the artisan what is tolerated, not why to change position 309. Under In re the Federal Circuit line on "obvious to try" (KSR, 550 U.S. 398; In re O'Farrell), that is a "try-every-parameter" theory, not a case of a finite, predictable set of identified solutions. Halozyme's answer brief made this concrete: the Petitioner's path required ~30–50 discrete steps (sequence retrieval, de-duplication, four MSA steps, variability analysis) — steps not disclosed in either reference.
• There is also a teaching-away / unpredictability overlay in the patent's own data: of 6,753 single substitutions reported, ~3,380 (57.13%) were inactive, and only ~10% had activity increased over wild-type. That is powerful evidence, as of the relevant date, that the effect of a given substitution in PH20 was not predictable — which undermines "reasonable expectation of success" for an unidentified position.

Net assessment of Ground A: it is a legally coherent prima facie case for the narrower dependent claims (a genus of PH20₁₋₄₄₇ variants with a single substitution in a non-essential region and ≥40% retained activity is squarely within the '429 patent's express teaching), and it is weak for claims 1–2 and the broad genus claims, where the claims are not limited to small numbers of substitutions and the required position-309 change is nowhere flagged. Note also a doctrinal weakness in the petition's framing: the argument that "the claims capture one obvious mutant (I309N), therefore the genus claims are unpatentable" is not, standing alone, a proper §103 theory for a broad genus claim — the claimed subject matter as a whole must be obvious. The Board's refusal to adopt the §103 ground is consistent with that.

Ground B — '429 + Chao + Zhang (2009)

Motivation: Zhang teaches that the Hyal-EGF domain (337–409) is necessary for hyaluronidase activity. Combining it narrows the "non-essential" set and gives a mechanistic reason to avoid certain regions. Gap: it still says nothing about position 309 (which lies outside 337–409), so it adds nothing toward the claim-defining limitation. Useful only as corroboration of the "essential residues" map.

Ground C — '429 + Chao + '457 publication, for the truncated-variant embodiments

Motivation: the '457 publication supplies the truncation–activity relationship and the glycosylation requirement (N200, N333, N358), which the claims' "C-terminal truncated fragment … soluble PH20" language implicates. Gap: the '457 publication shows truncation below ~442 is largely inactivating, which if anything argues against the claimed truncation subgenus (claims reaching down to ~419–430) being obvious-and-active; and it says nothing about position 309. This combination is better suited to a §112 attack (the one that actually succeeded) than to §103.

Ground D — the formulation / dosage-form / method claims (claims 30–40 and the composition claims)

These do not turn on position 309 alone; they require a modified PH20 "active mutant" in a preserved (phenolic) formulation, optionally with insulin, at defined concentrations/pH/salt.

• Motivation is comparatively strong and independent of the polypeptide-selection problem: multi-dose parenteral products require an antimicrobial preservative (phenol, m-cresol, benzyl alcohol, parabens are the standard phenolic set — the patent itself recites the conventional ranges at 0.05–0.6% w/v, consistent with the Remington/USP art), and co-formulations of a spreading agent with a fast-acting insulin in a pen/pump are conventional drug-delivery design choices. The claims recite routine parameters (7.0–7.6 pH; 0.1–200 mM NaCl; 10–1000 U/mL insulin).
• The genuine §103 gap: the point of the invention is that ordinary PH20 is not stable in phenolic preservatives; the patent's own Tables 11–12 show wild-type PH20 retaining only a few percent of activity in m-cresol. So a formulartion claim that requires the modified enzyme would be obvious only if the artisan had a reason to expect that the specified modification conferred preservative resistance — which loops back to Ground A's gap. Conversely, claims that merely recite a preserved formulation without tying the preservative-stability benefit to a particular modification are vulnerable as obvious combinations of (i) the selected modified PH20 and (ii) conventional preserved-formulation art.
• Note the record here too: the petition attacked the stability data as not probative (Tables 11–12 values within the range of the positive control; unmodified PH20 activity varying 87–97% between runs), and asserted no nexus between the claims and the commercial success evidence.

Ground E — nucleic acid, vector, cell, and screening-method claims

Claims to nucleic acids encoding the polypeptide, vectors, host cells (e.g., CHO), and methods of producing the polypeptide are ordinarily obvious if the polypeptide claim is obvious (In re the standard practice that a novel protein's encoding DNA is obvious where the protein is obvious and the sequence is enabled; no separate inventive weight). Likewise, claims to a "method for identifying a modified hyaluronan-degrading enzyme that exhibits stability under a denaturation condition" (test activity ± denaturant; select if activity in denaturant ≥5%/40% of activity without) recite a conventional screening/microturbidity assay workflow that the prior art (including the '429 patent's own screening and the USP microturbidity assay) already describes. These claims are the least resistant to §103, because they add nothing beyond routine assay design and the polypeptide genus's own obviousness; but again, if the position-309 genus itself survives §103, these fall with it.

4. Secondary considerations / nexus

• Commercial success: Halozyme's MDASE technology and berahyaluronidase alfa (in Keytruda Qlex™) are real. But the asserted product contains a multiply modified PH20; the petition argued there is no nexus between the claimed position-309 genus and the commercial product's success, because the product's performance reflects the combination of modifications, formulation and delivery improvements, not the single recited change. Expect this to remain the battleground if §103 is re-run.
• Unexpected results: the patent's own data (Tables 11–12) is the natural home for unexpected-results evidence (phenol/m-cresol resistance, activity at 37 °C), but the record shows it was attacked as within noise and as failing to identify which combinations improve stability. That is a factual dispute, not a legal certainty.

5. Bottom line

1. The most complete §103 combination the record supports is: the '429 patent (EX1005) in view of Chao (EX1006), with the artisan's ordinary knowledge of rational protein design and multi-sequence alignment. The motivation is explicit — the '429 patent teaches and expressly claims single substitutions in non-essential regions of PH20₁₋₄₄₇ with retained biological activity — and Chao supplies the structural/alignment toolkit to locate candidate regions. Add Zhang (2009) to map essential domains and the '457 publication for truncation/glycosylation constraints.
2. That combination does not reach position 309 on this record. Neither reference identifies position 309; "many amino acids occur here in homologs" establishes tolerance, not a reason to substitute; and the Petitioner's case rested on expert-driven MSA steps not disclosed in either reference. The Board expressly declined the §103 ground on that basis (PGR2025-00042 institution decision, §XI.C), while instituting on §112 (written description and enablement). Multiple PGRs in this family have since ended in unpatentability on §112 grounds, not §103 (see Venable and the family reporting).
3. Where a §103 attack is genuinely strong: (a) the narrow dependent claims reciting a small number of substitutions in a non-essential region of PH20₁₋₄₄₇ with ≥40% retained activity; (b) the nucleic acid/vector/cell/production and screening-method claims, which track the polypeptide plus routine molecular biology; and (c) formulation and method-of-use claims that do not tie the disclosed preservative-stability or dispersion benefit to the specific position-309 change — there, the motivation (multi-dose parenteral formulations, phenolic preservatives, insulin co-formulations in pens/pumps) is independent of the selection problem.
4. Two caveats I will not paper over. First, the board pages I retrieved render some claim lists inconsistently (the institution decision reportedly identifies "claims 3, 4, 6, and 34-40" as the instituted claims, while its §112 analysis discusses the broader sets "1-2, 5, 7-16, 25-27"), so I would verify the exact instituted claim set against the primary document before relying on it. Second, I do not have the verbatim, full text of claim 1 of US12037618 from the page you supplied; the "position 309 + identity + ≥40% activity + provisos" characterization above comes from the PGR petition/decision and family counterparts (e.g., US 2013/0302275 A1), which is reliable for orientation but is not the claim as issued.

If you want, I can draft the actual rejection-style §103 analysis (Ground A) as a claim chart mapping each limitation of claim 1 and representative dependent claims to the '429 patent and Chao, with the motivation and expectation-of-success statements quoted from the references.