US 9812542

I'll verify current details via search, then summarize.

Let me pull the actual claim language and check for any 2026 litigation activity involving this patent.

I have solid bibliographic data. Let me try to get the exact claim text.

US 9,812,542 B2 — Summary

Bottom line up front: I confirmed the bibliographic record below against the patent's own front page (PDF) and the Google Patents record. I could not retrieve the verbatim text of the '542 patent's own 18 claims, and I found no CAFC 2026 docket entry specifically naming US 9,812,542. Both points are flagged in the uncertainty note at the end.

Bibliographic data

Assignment trail noted on the record: Acorn Technologies, Inc. → Acorn Semi, LLC (June 26, 2019); a security interest to The Peter Norton Living Trust (May 30, 2019); release of that security interest and assignment to Oak IP, LLC (both December 26, 2024).

Continuation chain (per the '542 specification): a continuation of 15/048,877 (filed Feb. 19, 2016, now US 9,905,691), itself a continuation of 13/552,556 (US 9,425,277), ← 13/022,522 (US 8,431,469), ← divisional of 12/197,996 (US 7,884,003), ← divisional of 11/181,217 (US 7,462,860), ← continuation of 10/217,758 (US 7,084,423, filed Aug. 12, 2002). It is related to 10/342,576 (US 6,833,556).

Abstract (verbatim, as printed)

"An electrical device in which an interface layer is disposed in between and in contact with a conductor and a semiconductor."

(That is the entire abstract; the '542 shares its abstract with siblings such as the '261, '167, '691 and '395 patents, which also use the identical one-sentence abstract.)

Plain-language overview

The patent is about improving metal–semiconductor contacts by inserting a very thin interface layer between the metal and a silicon-based semiconductor (Si, SiC, SiGe). The layer does two jobs: (1) it passivates the semiconductor surface by terminating dangling bonds (which otherwise create surface states), and (2) it separates the metal far enough from the semiconductor to suppress metal-induced gap states (MIGS) — the mechanism the patent credits (following Tersoff 1984) with pinning the semiconductor's Fermi level near mid-gap.

Together, those two effects "depin" the Fermi level, so the Schottky barrier height becomes tunable by choosing the metal's work function rather than being fixed by surface effects. The key insight in the specification is a trade-off (illustrated in Fig. 8): too thin an interface layer and MIGS still pin the barrier; too thick and tunneling current is choked off. There is therefore an optimum thickness at which specific contact resistance is minimized. The patent reports minimum specific contact resistances of ≤ ~10 Ω-μm², or even ≤ ~1 Ω-μm², and in the Summary also lists ≤ 2500, 1000, 100, 50, 10 and 1 Ω-μm².

Passivation materials contemplated include nitrides, oxides, oxynitrides, hydrides, arsenides and fluorides (e.g., H, O, N, As, F); for H/As/F, a separate "separation layer" may be required. Nitrogen-based formation is described in detail (annealing at ~300–750 °C in NH₃ for a self-limiting low-temperature nitride; or UHV annealing at ~900–1000 °C with a short NH₃ pulse so growth self-terminates at sub-nanometer/monolayer thickness). Hydrogen/fluoride passivation via HF immersion is also described. The patent further describes using the junction in diodes (Schottky diodes, including high-voltage diodes able to sustain high reverse bias) and in FET source/drain contacts, and notes the ability to select metals that do not form silicides because passivation is handled by the interface layer rather than by silicidation.

Independent claims — status of my information

I do not have authoritative verbatim text of the '542 patent's independent claims. The text of this patent supplied to me (Google Patents rendering) is truncated after the detailed description and does not include the claims, and the front-page PDF search result confirms only "18 Claims."

The claim language that surfaced in my searches — e.g., "An electrical device, comprising: a silicon-based semiconductor of either n-type or p-type semiconductor material; a metal having a workfunction approximately equal to a conduction band…; and an interface layer disposed between and in contact with both the semiconductor and the metal, wherein the electrical device has a specific contact resistance of less than or approximately equal to 1000 Ω-μm²," and the "depin a Fermi level of the conductor in the vicinity of the junction" claims — belongs to the related '423 patent (US 7,084,423) and its prosecution history, not to the '542 patent. Similarly, the accused "metal oxide / oxide of titanium" claims found in the IPR briefing are from other family members (the '395 and '261 patents), not the '542. I am therefore not attributing those claims to US 9,812,542.

What I can say with confidence, based on the shared specification and the '542's own Summary of the Invention, is the subject matter the '542 claims are drawn to: an electrical device / electrical junction in which an interface layer (passivating material, optionally plus a separation layer) sits between and in contact with a conductor (metal) and a silicon-based semiconductor, configured to depin the Fermi level of the semiconductor while still passing current, with specific contact resistance limits (≤ ~10 Ω-μm², or ≤ ~1 Ω-μm², and the broader ladder of thresholds); and nitrided-interface-layer embodiments formed by heating in a nitrogenous ambient (NH₃, N₂, plasma-generated N). The exact wording, dependency structure and the number of independents among the 18 claims should be verified against the patent's claim set on USPTO PatentCenter (or the front-page PDF, which lists 18 claims and 6 sheets).

Litigation / CAFC 2026 check

• CAFC 2026 dockets: My search of Federal Circuit 2026 materials (including the court's June 2026 scheduled-cases list and 2026 opinion roundups) returned no case specifically identifying US 9,812,542. This is a negative finding, not proof of nonexistence — Federal Circuit docket entries are often captioned by party name rather than patent number, so a case involving this patent could exist under a party caption I did not surface.
• Known contentious history (family-level): The specification family has a Google Patents "Family has litigation" flag. The public record shows Acorn Semi, LLC v. Samsung (E.D. Tex., complaint filed October 23, 2019) asserting several Acorn patents, which spawned a set of IPRs (e.g., IPR2020-01182, -01207, -01279, -01241, -01282). The '542 patent appears in those proceedings principally as an ancestor in the priority chain (it is recited as "CON of 15/251,210 08/30/2016 PAT 9812542" in the continuation data of later applications), and it was also cited as a double-patenting reference during prosecution of a later family member.

Uncertainty disclosure

1. Claim text: Not verified verbatim for the '542 patent. Treat the claim overview above as an inference from the shared specification, not as the literal claim language.
2. CAFC 2026: No 2026 Federal Circuit docket specifically naming 9,812,542 was found; I cannot rule out an unnamed/party-captioned appeal.
3. Assignee/status: "Oak IP LLC" as current assignee and "Expired – Fee Related" come from the Google Patents record, which itself disclaims that legal status is an assumption. Confirm on USPTO PatentCenter/Assignment records if this matters for your purpose.
4. The "anticipated expiration 2022-08-12" figure reflects the 20-year term running from the 2002 priority filing, consistent with the patent's expired status; it should be treated as an approximation, not a legal conclusion.

I'll research litigation involving US Patent 9,812,542. Let me search several sources.

Let me search more specifically for the patent owner and known litigation campaigns.

I found the key owner (Acorn Semi) and its Samsung case. Now I need to verify whether the '542 patent itself was specifically asserted. Let me dig deeper.

Litigation Search Report: U.S. Patent No. 9,812,542

Summary Answer

Based on my searches, I found no litigation that specifically asserts U.S. Patent No. 9,812,542 ("the '542 patent"). However, the '542 patent belongs to a patent family that has been litigated extensively, and Google Patents flags the family as having litigation (via Darts-IP family ID 31495225). I want to be precise about the distinction below.

The '542 Patent and Its Owner

• Patent: US 9,812,542 B2 — "Method for depinning the Fermi level of a semiconductor at an electrical junction and devices incorporating such junctions"
• Inventors: Daniel E. Grupp; Daniel J. Connelly
• Application: 15/251,210, filed Aug. 30, 2016; granted Nov. 7, 2017
• Priority date: Aug. 12, 2002
• Assignee chain: Acorn Technologies, Inc. → Acorn Semi, LLC → (per Google Patent's recorded assignments) Oak IP LLC is listed as current assignee
• Status: Expired – Fee Related (anticipated expiration Aug. 12, 2022 recorded)

The Family Litigation (Not the '542 Patent Itself)

The relevant family litigation is:

Acorn Semi, LLC v. Samsung Electronics Co., Ltd., et al.

• Plaintiff: Acorn Semi, LLC
• Defendants: Samsung Electronics Co., Ltd.; Samsung Electronics America, Inc.; Samsung Semiconductor, Inc.; Samsung Austin Semiconductor, LLC
• Jurisdiction: U.S. District Court for the Eastern District of Texas, Marshall Division (Judge Rodney Gilstrap)
• Case No.: 2:19-cv-00347-JRG
• Filed: October 23, 2019
• Patents actually asserted: U.S. Patent Nos. 7,084,423; 8,766,336; 9,209,261; 9,461,167; 9,905,691; and 10,090,395
• Outcome/Status: Jury trial began May 13, 2021; on May 19, 2021 the jury found Samsung infringed all asserted claims and awarded Acorn $25 million (lump-sum royalty). The court denied Acorn's $6.7M fee request (Feb. 17, 2022). Samsung appealed to the Federal Circuit (Appeal No. 22-1499). The parties settled in January 2023 while the appeal was pending.

Critically, the '542 patent was NOT among the patents asserted in this case, even though it is in the same family. The '542 patent is a continuation ancestor of the asserted '691 and '395 patents (both the '691 and '395 descend from application 15/251,210, which issued as the '542 patent).

Related PTAB Proceedings

Samsung filed a series of IPRs against the Acorn family patents that were asserted (e.g., IPR2020-01207, IPR2020-01279, IPR2020-01282, IPR2019-01182, IPR2020-01182, and others). These covered the '423, '336, '261, '167, '691, and '395 patents. I found no IPR petition directed at the '542 patent.

Confidence and Caveats

• High confidence: The '542 patent was not asserted in Acorn Semi v. Samsung (2:19-cv-00347-JRG), because the complaints, invalidity contentions, trial verdict, and related pleadings I located all enumerate a fixed set of asserted patents that excludes the '542 patent.
• Lower confidence / not fully verified: I was not able to run a complete, authoritative docket search (e.g., a full Darts-IP family query, a PACER/RECAP name search for "9,812,542" across all districts, or a Unified Patents portal query), because my tool access was limited. It is therefore possible that the '542 patent was asserted in a separate or later action (e.g., a subsequent Acorn/Oak IP campaign) that did not surface in my searches.
• Note the assignee changes: as of 2024 the patent records reflect assignment to Oak IP, LLC, which may indicate a separate assertion campaign that I could not confirm. I recommend verifying directly on the Unified Patents litigation portal, Darts-IP (family 31495225), and PACER/RECAP using the literal patent number "9812542."

Bottom line: I cannot confirm any lawsuit asserting U.S. Patent No. 9,812,542 specifically. The prominent Acorn Semi v. Samsung litigation (E.D. Tex. 2:19-cv-00347-JRG) involved the same patent family but asserted different patents (the '423, '336, '261, '167, '691, and '395). If a case does exist for the '542 patent, it did not appear in the sources I was able to search.

I'll start by checking the structured list (which is the canonical source) and then run web searches to surface anything the ODP ingest may have missed.

The first pass surfaced the 2020 Acorn/Samsung IPR family, but on sibling patents ('423, '261, '336, '167, '691, '395) — not '542. Let me run targeted searches on '542 itself and on the litigation/appeal chain.

Important lead: '542 is a family member (it's in the priority chain of the '691 patent), and there's a 2025 Oak IP v. GlobalFoundries campaign asserting "three patents, including the '691 Patent." I need to find whether '542 is one of them and whether GF petitioned against it.

Proceedings overview

Total AIA trial proceedings naming US 9,812,542 as the challenged patent: 0. The canonical ODP "PTAB proceedings on file" block returns no AIA trials, and my independent web search failed to surface any IPR, PGR, or CBM in which the '542 patent is the patent under review. Breakdown by status is therefore: active 0 / claims invalidated 0 / claims sustained 0 / settled 0 / institution denied 0.

Defensive posture: The '542 patent is untested at the PTAB — it has never been narrowed, never been construed by the Board, and no § 315(e) estoppel attaches to anyone. That is not the same as "hardened." The more consequential fact for a defendant is that, per the patent record, the '542 patent expired on 2022-08-12 (20 years from the 2002-08-12 priority date; Google Patents lists status "Expired - Fee Related" / "2022-08-12 Anticipated expiration"). An expired patent can still be asserted, but only for past damages within the 35 U.S.C. § 286 six-year lookback, and its claims can still be challenged in an IPR. The real question for any demand letter citing '542 is not "will I win an IPR" but "what pre-2022-08-12 conduct is even in play."

No proceeding found — and why that is itself informative

There is no {PROCEEDING_NUMBER} to report. Rather than leave the analysis empty, here is the record that establishes the absence, plus one item you should verify before relying on it.

1. The family was heavily litigated — on siblings, not on '542.
Acorn Semi, LLC sued Samsung in E.D. Tex. (Acorn Semi, LLC v. Samsung Electronics Co., Ltd., No. 2:19-cv-00347-JRG, filed 2019-10-23). Acorn's P.R. 3-1 infringement contentions asserted exactly six patents — and '542 was not among them:

• 7,084,423 (claims 62-64, 66)
• 8,766,336 (claims 1-16, 65-80)
• 9,209,261 (claims 1-3, 17-18, 21-24)
• 9,461,167 (claims 1-6, 8-16)
• 9,905,691 (claims 1-4, 6, 8, 10-13, 15-20, 22, 25-30)
• 10,090,395 (claims 1-6, 8-9, 11-12, 14-28)

Source: Acorn's Infringement Contentions, Ex. 1024 to IPR2020-01182 (docketalarm).

2. Samsung's 2020 IPR wave mapped 1:1 to the asserted siblings — never to '542.
The related-proceeding list in the Board's institution decision in IPR2020-01206 names: IPR2020-01182 ('423), IPR2020-01183 ('261), IPR2020-01204 and IPR2020-01264 ('336), IPR2020-01205 and IPR2020-01241 ('167), IPR2020-01206 and IPR2020-01279 ('691), IPR2020-01207 and IPR2020-01282 ('395). See PTAB-IPR2020-01206-22 at 5. Ten petitions, six patent numbers — none of them '542.

3. '542 appears in the PTAB record only as a family member, not a target.
In the IPR2020-01206 petition, Samsung listed patents "that purport to claim the benefit of the priority of the filing date of the '691 patent," and the very first entry is "U.S. Patent No. 9,812,542 — August 30, 2016." Id. That is a priority-chain citation, not a challenge.

4. The 2025 re-monetization campaign also did not include '542.
Acorn's portfolio moved to Oak IP, LLC (Rule 7.1 disclosure: parent Monument Patent Holdings, LLC; affiliate Dominion Harbor Enterprises, LLC) in December 2024. Oak IP then sued GlobalFoundries in D. Del., Oak IP, LLC v. GlobalFoundries Inc., No. 1:25-cv-00142 (filed 2025-02-04) — the AO-120 report lists exactly three patents: 9,905,691; 10,090,395; 10,937,880. No '542. The case was stayed and then dismissed by stipulation (D.I. 17, entered 2025-09-02, Judge Maryellen Noreika). GF's responsive 2025 IPR wave (e.g., IPR2025-00889, filed 2025-05-13; IPR2025-01129 on the '880 patent) likewise does not name '542 as the challenged patent.

⚠️ One item to verify before you file

Search turned up an exhibit list in IPR2025-00889 (GlobalFoundries Inc. v. Oak IP LLC) containing:

• Ex. 1016 — File History of U.S. Patent No. 9,812,542
• Ex. 1017 — U.S. Patent No. 9,812,542

Source: ipverse.greyb.com case page for IPR2025-00889.

I could not confirm from the available results whether '542 is the challenged patent in IPR2025-00889 or merely cited as a family/priority exhibit (which is how '542 shows up everywhere else in this family's record — and note the pairing with '542's own file history is equally consistent with either reading). Two facts argue it is not the challenged patent: (a) Oak IP did not assert '542 against GF, removing any obvious motivation to petition on it; and (b) ODP — your canonical source — reports no proceeding on this patent. Verify directly on PTAB E2E / P-TACTS before relying on "zero proceedings" in any filing or opinion. If IPR2025-00889 does target '542, note it would be a post-expiration challenge, and the Board would apply Phillips construction.

Strategic summary

Claim status: everything is UNTESTED. No claim of '542 has been canceled, confirmed, or even construed by the PTAB. Do not let anyone tell you "claims 1-5 are dead" or "the patent survived two IPRs" — both statements are false as to this patent. The narrow-the-patent-by-IPR playbook that worked against the siblings has simply never been run against '542.

Estoppel: clean slate, but also a clean target. Because no IPR was ever instituted on '542, there is no § 315(e)(2) estoppel against anyone, and no § 325(d) "same art previously considered" problem to defuse. Any defendant within its § 315(b) one-year window can file a first-position IPR using any patents/printed publications. The obvious starting kit is the art that already proved potent against the siblings — Grupp '483, Goodnick & Taubenblatt, and Jammy all appear in the Samsung/GF petitions and are natural § 102/§ 103 candidates here given the near-identical specifications across the family. The Board's priority holdings on siblings are a real roadmap: in IPR2020-01206 the panel found that the "oxide of titanium" genus lacks written-description support in ancestor applications and that claims reciting "specific contact resistivity . . . less than 1 Ω·μm²" are not enabled by the 2002 priority document (so Grupp '483 became prior art to those claims) — GF later quoted that ruling verbatim in its '880 petition.

Context on the family (not '542 specific, use with care). A May 2021 E.D. Tex. jury found Samsung infringed the sibling patents and awarded Acorn at least $25 million; the PTAB then issued a round of Final Written Decisions on 2022-01-12/13 (IPR2020-01206 and -01279 on the '691 patent; IPR2020-01207 and -01282 on the '395 patent, the latter before APJs John R. Kenny, Brian J. McNamara, and Aaron W. Moore, with the opinion authored by Judge Kenny). Law360 characterized the outcome as Samsung "striking down some" claims tied to the $25M loss, i.e., a partial invalidation. Samsung appealed to the Federal Circuit in Nos. 2022-1539, -1540, -1541, and -1542, with an Acorn cross-appeal referenced at No. 2022-1499 — I could not verify the dispositions of those appeals from searchable sources and will not guess at them. Whether any of those decisions formally held a given sibling claim unpatentable should be confirmed against the FWDs on USPTO PTAB Decisions rather than from secondary coverage.

Pattern signals. Same petitioner, many petitions: Samsung filed a staggered multi-patent campaign (two petitions per patent on the '336, '167, '691, and '395 patents), and Acorn litigated the IPRs aggressively — its responses argued Appointments Clause violations, structural Office bias, and improper stipulation practices. That is an owner that fights, not one that settles. There is no defensive aggregator in this chain (no Unified Patents filing found). The current owner is a monetization entity (Oak IP / Monument Patent Holdings / Dominion Harbor), which means the assertion risk persists even though '542 itself has not yet been asserted.

Recommended next steps

1. Confirm the '542 record on PTAB E2E today and screenshot it. The only open question is IPR2025-00889 (GF v. Oak IP) and whether Exs. 1016-1017 are priority evidence or the challenged patent. Resolve that before you characterize '542 as "never challenged."
2. Lead with expiration, not validity. '542's anticipated expiration is 2022-08-12. Any damages case is limited to pre-expiration conduct within the § 286 six-year window. Build the demand-letter response around the absence of actionable pre-2022 activity — it is cheaper and more certain than an IPR.
3. If you do file an IPR, you are filing the first one — no § 325(d) headwind from prior Office consideration of the same art, and no § 315(e) estoppel constraining you. Start from Grupp '483, Goodnick & Taubenblatt, and Jammy, and mine the Samsung and GlobalFoundries petitions (IPR2020-01182/01183/01204/01205/01206/01207/01279/01282 and IPR2025-00889/01129) for the experts' claim-chart work on the near-identical specifications.
4. Check § 315(b) immediately. If you have been served with a complaint asserting '542, the one-year bar clock is running; a post-expiration IPR is still institution-eligible, and the Board will apply Phillips claim construction.
5. Do the priority-date diligence. The Board has twice held that family claims reciting "oxide of titanium" and the "< 1 Ω·μm²" resistivity range are not entitled to the 2002 priority date. If '542 contains comparable claims, Grupp '483 and other 2003-2015 art become available against them — a materially larger prior-art field than the 2002 date suggests.
6. For settlement leverage, note that Oak IP dismissed the GF case by stipulation on 2025-09-02 shortly after GF filed its 2025 IPR wave. That is the observed pattern for this owner: file the IPRs, then the district court case goes away.

I'll research the assignment chain, the parties, and any litigation before building the report.

Good — I have strong litigation and assignee data. Let me pin down the complaint date, the correspondent of record, and Acorn's corporate background.

Ownership & Assignment Analysis — US 9,812,542 B2

Verification starting points: USPTO Assignment Center · Google Patents legal events for US9812542B2 (legal-status/reassignment feed) · PTAB IPR2025-01129 mandatory notice identifying Oak IP's ultimate parent

Data limitation up front: I could not retrieve the reel/frame numbers or the recorded correspondent names for this patent's post-issuance records. USPTO's Assignment Center is not indexed in a way my searches could return, and the Google Patents reassignment feed does not publish reel/frame or correspondent fields. Every other element below (dates, conveyance types, assignors, assignees) is taken from the Google Patents legal-events feed and corroborated with PTAB/docket records. I have deliberately left reel/frame and correspondent blank rather than fabricate them. Those two fields must be pulled directly from Assignment Center using the "Search by Patent Number" function.

Inventors

Source: the '758 parent, U.S. Pat. No. 7,084,423, and the face of grandparent U.S. Pat. No. 6,833,556 ("Assigned to Acorn Technologies, Inc., Pacific Palisades, Calif.").

Pattern note — inverse of the usual red flag. There is no inventor-departure pattern here. Both inventors remained attached to the assignee and continued to be named on continuation filings for 15 years after the 2002-08-12 priority filing (e.g., application 15/418,360, filed 2017-01-27; 15/981,594, filed 2018-05-16). This is a founder-inventor portfolio that stayed intact with the original company through the entire prosecution chain — which sharpens, rather than weakens, the later transfer signal, because the inventors never became the sellers.

Original assignee

Acorn Technologies, Inc. (Santa Monica, CA → Pacific Palisades, CA → La Jolla, CA across filings; Palo Alto, CA by 2019).

• Line of business: Semiconductor technology development and IP licensing — a fabless/development-stage firm built around the founders' "passivated Schottky barrier" / Fermi-level-depinning technology. It is not a chip manufacturer.
• Product embodying the claims: No evidence of a commercial product. All detectable downstream activity is prosecution, licensing, and enforcement, not shipping product. This is the weakest-grounded statement in this report and is flagged as such: Acorn was a private company, so there are no SEC filings to confirm or deny product revenue.
• Current status: Operating as a holding/parent entity. In the 2019 Samsung litigation Acorn Semi, LLC's Rule 7.1 disclosure identified Acorn Technologies, Inc. as its corporate parent. Acorn Technologies, Inc. still appears as a party to the 2024-12-26 release-of-security-interest recordings.

Assignment timeline

All five post-issuance recordings below are taken from the Google Patents reassignment feed. Dates shown are as reported by that feed and I could not independently confirm whether each is the execution date or the recording date. Reel/frame and correspondent are not published in that source and are unavailable to me — noted individually. No bankruptcy, merger, or change-of-name conveyances appear in the chain.

1. 2019-05-30 / recorded 2019-05-30

• Reel/Frame: not retrievable (see limitation note)
• Conveyance: Security Interest (per Google Patents: "SECURITY INTEREST")
• Assignor: Acorn Semi, LLC
• Assignee: The Peter Norton Living Trust dated April 28, 1989
• Correspondent: not retrievable
• Context: Securitization — the Peter Norton Living Trust takes a security interest in the patent as collateral, i.e., a private financing/investor lien, not a transfer of title.

2. 2019-06-26 / recorded 2019-06-26

• Reel/Frame: not retrievable
• Conveyance: Assignment of Interest
• Assignor: Acorn Technologies, Inc.
• Assignee: Acorn Semi, LLC
• Correspondent: not retrievable
• Context: Internal reorg — carve-out of the patent portfolio into a dedicated subsidiary. Note the sequencing oddity: the security interest (item 1) is recorded three weeks before the assignment that ostensibly put title in the grantor of that security interest. That inversion is worth pulling the underlying documents to explain.

3. 2024-12-26 / recorded 2024-12-26

• Reel/Frame: not retrievable
• Conveyance: Assignment of Interest
• Assignor: Acorn Semi, LLC
• Assignee: Oak IP, LLC
• Correspondent: not retrievable
• Context: Transfer-to-asserter — the operating/enforcement entity sells the portfolio to a Dominion Harbor affiliate.

4. 2024-12-26 / recorded 2024-12-26

• Reel/Frame: not retrievable
• Conveyance: Release by Secured Party
• Assignor: The Peter Norton Living Trust dated April 28, 1989
• Assignee: Acorn Semi, LLC
• Correspondent: not retrievable
• Context: Lien cleanup — the Norton trust discharges its security interest in connection with the sale to Oak IP.

5. 2024-12-26 / recorded 2024-12-26

• Reel/Frame: not retrievable
• Conveyance: Release by Secured Party
• Assignor: The Peter Norton Living Trust dated April 28, 1989
• Assignee: Acorn Technologies, Inc.
• Correspondent: not retrievable
• Context: Lien cleanup — parallel discharge covering the parent entity, recorded the same day as the sale and the other release.

Term note: the '542 patent's anticipated expiration is 2022-08-12 (20 years from the 2002-08-12 priority), and its status on the feed is "Expired — Fee Related." The patent was therefore already expired (or expiring) when it reached Oak IP in December 2024. The commercial value in the 2024 transaction is the unexpired family members ('691, '395, '880, '748), not '542 itself.

Timeline diagram

timeline
    title Ownership of US 9812542
    2002 : Parent application filed by Acorn Technologies
    2017 : Patent US 9812542 issues
    2019 : Norton Trust records security interest
         : Acorn Technologies assigns to Acorn Semi LLC
         : Acorn Semi sues Samsung in EDTX
    2021 : Jury awards Acorn Semi 25 million dollars
    2022 : Patent reaches anticipated expiration
    2024 : Acorn Semi assigns portfolio to Oak IP LLC
         : Norton Trust releases the security interests
    2025 : Oak IP sues GlobalFoundries in Delaware

NPE / troll-pattern signals

1. Shell-entity transfer — PRESENT.
The terminal assignee, Oak IP, LLC, is a single-purpose licensing vehicle. Per its own mandatory notice in IPR2025-01129: "OAK IP LLC is a wholly-owned subsidiary of Monument Patent Holdings, LLC, which is a wholly-owned subsidiary of Dominion Harbor Enterprises, LLC," with a place of business at "812 W. McDermott Dr. #1026, Allen, TX 75013" — a private-mailbox-style address. The name suffix ("IP"), the two-tier holding structure, the mailbox address, and the absence of any product all align. Recorded via the 2024-12-26 assignment from Acorn Semi, LLC.

2. Known asserter in the chain — PRESENT.
Dominion Harbor Enterprises, LLC is the ultimate parent of Oak IP (IPR2025-01129 notice, dated June 13, 2025) and is a widely tracked patent-monetization firm; Oak IP appears as assignee on the Unified Patents portal for this family. Separately, the predecessor Acorn Semi, LLC is itself a high-frequency plaintiff: it sued Samsung on 2019-10-23 (2:19-cv-00347-JRG, E.D. Tex.), won a $25M jury verdict on 2021-05-19, and faced six Samsung IPRs (IPR2019-01182, IPR2020-01207/-01279/-01282, etc.). Chains terminating at an entity the Unified Patents / RPX directories list is a direct match to this signal.

3. Repeat correspondent across the chain — UNCLEAR / NOT DETERMINABLE.
The recorded correspondent of record for the 2019 and 2024 recordings is not published in the sources available to me. I am not going to substitute litigation counsel for the assignment correspondent — they are different records and conflating them would be fabrication. This signal cannot be scored until Assignment Center is queried for all five reels.

4. Cascading transfers (<24 months, chained LLCs) — NOT PRESENT.
The title transfers are 2019-06-26 and 2024-12-26 — roughly five and a half years apart. There is no rapid LLC-to-LLC cascade. The three December 2024 recordings are a single-day closing package (one sale plus two lien releases), not a chain.

5. Pre-litigation transfer — PRESENT.
The assignment from Acorn Technologies, Inc. to Acorn Semi, LLC is recorded 2019-06-26. Acorn Semi filed against Samsung on 2019-10-23 — an interval of under four months, inside the six-month window. The patent was moved into the asserting entity immediately before suit, producing a clean standing record in the plaintiff's name. (The complaint's Rule 7.1 statement confirming Acorn Technologies as parent confirms the transfer was an enforcement-structuring step, not an arm's-length sale.)

6. Bankruptcy fire-sale — NOT PRESENT.
No Chapter 7/11 filing by any assignor appears in the record. The 2024 exit was a negotiated portfolio sale to Dominion Harbor, and the Norton trust lien was released by agreement — not a court-supervised sale.

7. Privateering — UNCLEAR.
Superficially present: Acorn Technologies (the developer) moved the patents to Acorn Semi, LLC, its own wholly-owned enforcement arm, which then sued Samsung. But "privateering" strictly requires an operating company with commercial product transferring to an NPE to attack competitors, and Acorn's status as a shipping operating company is unverified (no SEC filings; private company). Scored unclear rather than present, per the no-speculation rule.

8. Defensive aggregator — NOT PRESENT.
The chain terminates at an active plaintiff (Oak IP), not at RPX, AST, LOT, Unified Patents, or OIN. The inverse signal applies.

Verdict

NPE — high confidence.

Three independently sufficient strong signals converge. (1) Shell-entity transfer: title lands in Oak IP, LLC by the 2024-12-26 assignment, and Oak IP's own PTAB filing in IPR2025-01129 confirms it is a wholly-owned subsidiary of Monument Patent Holdings → Dominion Harbor Enterprises at a mailbox address in Allen, TX. (2) Known asserter in the chain: Dominion Harbor is a tracked monetization entity, and predecessor Acorn Semi, LLC is itself a defendant-facing plaintiff that took a $25M verdict against Samsung on 2021-05-19. (3) Pre-litigation transfer: the 2019-06-26 assignment into Acorn Semi, LLC precedes the 2019-10-23 Samsung complaint by under four months. The chain is packaged as pure enforcement assets — the patent itself expired 2022-08-12 and was sold in 2024 only as part of a live continuation family ('691/'395/'880) that Oak IP asserted against GlobalFoundries in D. Del. 1:25-cv-00142 on 2025-02-04.

Residual gaps that a manual Assignment Center pull would close: the reel/frame numbers for all five recordings, and the correspondent of record — the single most probative field for signal #3, which I could not score. Query Assignment Center by patent number and compare the correspondent across the 2019 and 2024 recordings against Dominion Harbor's other reels; recurrence there would convert an already high-confidence NPE call into a documented one.

I'll research US Patent 9812542 and its cited prior art references.

Let me gather the specific patent citations listed for US9812542.

Let me look for the specific cited references listed on the patent's citation pages.

Note on tool limits

I hit the search-step cap before I could pull the complete front-page "Patent Citations" (U.S./foreign patent-document) table for US 9,812,542 directly. Below I give (a) what I positively verified about the patent, (b) the cited references I did retrieve, with the caveats flagged explicitly, and (c) a § 102 mapping. Where I could not verify a citation, I say so rather than fabricate one.

1. Identification of the target patent (verified)

Claim subject matter (from the specification/family): electrical device with an interface layer between and in contact with a metal and a silicon-based semiconductor configured to depin the Fermi level while permitting current flow; specific contact resistance < ~10 Ω-μm² (or ≤1 Ω-μm²); interface layer = nitride/oxide/oxynitride/arsenide/hydride/fluoride, optionally a separation layer; may be a monolayer; limitations reciting titanium, arsenic, metal oxide, etc.

2. What "citations for 9812542" actually are — an important caveat

There are three distinct sets, and the request conflates them:

1. References cited in the patent ("References Cited") — prior art listed on the face of the patent / considered during prosecution. Because US 9,812,542 is a continuation with a 2002 priority, most of its cited art appears as Non-Patent Literature (NPL) on the Justia "References Cited" list, which I retrieved.
2. Patent documents cited (US/EP/JP/WO) on the front page — I could not fully verify this table.
3. Forward citations ("Cited By") — later patents citing 9,812,542 (e.g., US 10,388,748; US 10,090,395; US 10,186,592; US 11,056,569; US 11,018,237; US 10,950,707; US 10,937,880; US 11,355,613 — all Acorn family members). These are not prior art to 9,812,542 (they post-date 2002).

3. Cited references retrieved (Non-Patent Literature, per Justia "References Cited" for 9812542)

For each: full citation, date, brief description, and potential § 102 relevance. All dates are 2002 or earlier and therefore pre-date the Aug. 12, 2002 priority date — they are the references the examiner/patentee placed of record.

(The Justia list also shows "et al." entries I could not fully resolve — e.g., additional "…" truncated items — so this table may be incomplete.)

4. Patent-document citations (partially verified — flagged)

I could not confirm these belong to the 9,812,542 front page rather than to a sibling application's search report; treat with caution:

I was unable to verify the complete U.S. patent-document citation table for 9,812,542. I am not going to invent entries. If you need the authoritative list, the definitive sources are the USPTO PatentCenter "References Cited" tab for application 15/251,210 and the Google Patents "Patent Citations" table — both of which I could not fully load within the tool limit.

5. § 102 assessment (best-effort)

A key caution: every reference above was already of record and was overcome — 9,812,542 issued over them. So calling any of them "anticipating" is speculative. On the merits:

• No single cited reference anticipates the independent claim(s). Each misses at least one element: the cited NPL is either (a) theory/modeling (Tersoff, Louie, Keller), (b) a non-Si material system (Kim/InGaP, Okamoto/GaAs), (c) a non-contact structure (McKee gate oxide), or (d) background on pinning (Shalish, Padovani).
• Closest single-reference candidates for a § 102 challenge to narrower dependent claims:
  • Kim et al. (1997) — sulfur-passivated contact with metal-dependent Fermi-level movement (depinning concept, but InGaP).
  • "Metal/Silicon Schottky Barrier Lowering by RTCVD Interface Passivation" (2000) — metal/Si barrier lowering by an interface layer (element-by-element closest, but likely lacks the specific-contact-resistance and monolayer/separation-layer limitations).
  • Schmidt et al. (1999) — Si/SiN passivation (nitride interface-layer limitation).
  • Okamoto et al. (1998) — thin interlayer → near-ohmic low-resistance contact.
• § 103 combinations are the realistic invalidity theory (e.g., Kim/Okamoto passivation teachings + Padovani metal–Si junction + Schmidt SiN), which is consistent with the IPR2020-01182/01206/01207 proceedings against Acorn. Note Kedzierski (2003) and the WO 2006/012042 / WO 2005/103376 documents post-date the 2002 priority and are not available as prior art against 9,812,542.

Bottom line / honesty statement

I positively verified the identity, priority, inventors, and assignment of US 9,812,542 and retrieved a substantial set of its "References Cited" (NPL). I could not fully verify the complete front-page patent-document citation table, so I have not fabricated those entries. For a filing-grade § 102 chart you should pull the authoritative list from USPTO PatentCenter (application 15/251,210 → "References Cited") or the Google Patents "Patent Citations" table and the IPR2020-01182/01206/01207 petitions, which contain the actual invalidity mappings.

I'll gather the claim set and the cited prior art for US 9812542 before analyzing.

I need the claim text and the cited prior art list from the Google Patents "References Cited" section. Let me pull those.

Let me get the actual claims of US 9,812,542 and the prior art actually asserted against this family in PTAB proceedings.

Obviousness Analysis — US 9,812,542 B2 under 35 U.S.C. § 103

0. What I could and could not verify (read this first)

The authoritative text I was given (the Google Patents "full text" of US 9,812,542) supplies the abstract, summary, figures list, and detailed description, but it is truncated before the claims and it does not contain the page's "References Cited / Prior Art" citation table. Two search passes also failed to surface a citation list for this specific patent. So:

• Verbatim claim language of the '542 patent: not retrieved. My claim analysis is keyed to (i) the summary of the invention in the patent text, (ii) the Google Patents chemical-entity/term tables for this patent (which show that "titanium" appears in ~7 claims, "arsenic" in ~3, "metal oxide" in ~3, "single layer"/monolayer in ~13, "separation layer" in ~10 — these are term counts, not claim text), and (iii) the closely parallel claim set of sibling US 10,090,395, which I could retrieve.
• Prior-art citation list: not retrieved. I therefore build the analysis from (a) the references the '542 specification itself cites/admits, (b) references documented in the PTAB record for this patent family (the "Grupp" depinning family), and (c) standard treatises. Everything below is flagged as to provenance. Where I rely on memory for a title or date, I say so.
• Per the operating rule, I have not "corrected" any identifier. Identifiers are reproduced exactly as found in the sources.

1. The invention, in claim-feature terms

Taking the patent at face value (col. citations = the specification text supplied):

The '542 issued from application 15/251,210 (filed 2016‑08‑30), a continuation of 15/048,877 (filed 2016‑02‑19), which chains back to 10/217,758 (filed 2002‑08‑12). Because at least one claim necessarily has an effective filing date after 16 March 2013 (e.g., anything reciting "oxide of titanium"), the AIA §§ 102/103 apply to this patent.

2. Prior art relied on

A. Admitted/cited in the '542 specification itself (Applicant Admitted Prior Art; MPEP 2129):

• Schottky's 1938 barrier model; Bardeen's surface-state pinning model; Grondahl & Geiger (1926).
• Tersoff, "Schottky Barrier Heights and the Continuum of Gap States," Phys. Rev. Lett. 52(6), Feb. 6, 1984 — the MIGS/gap-center mechanism.
• Heine; Flores & Tejedor; Louie, Chelikowsky & Cohen, "Ionicity and the theory of Schottky barriers," Phys. Rev. B 15, 2154 (1977).
• The patent also admits the trade-off: too thin → resistance rises "because of the presence of MIGS"; too thick → tunneling-limited. That admission is central to the § 103 case below.

B. Documented in the family's PTAB record (from the '395/’880/’691 IPR papers retrieved):

• Rhoderick & Williams, Metal-Semiconductor Contacts (cited as Ex. 1023 "Rhoderick" in the Samsung IPR declaration).
• S.M. Sze, Physics of Semiconductor Devices, John Wiley & Sons (1981) — the standard text on Schottky/tunnel contacts and specific contact resistance.
• US 7,084,423 (Grupp & Connelly; from application 10/217,758 — expressly identified in the '542's Related Applications section as "now U.S. Pat. No. 7,084,423"); likewise US 7,462,860, US 7,884,003, US 8,431,469, US 9,425,277 — all named family members whose specifications are incorporated by reference into the '542.
• US 7,176,483 ("Grupp '483") — identified in GlobalFoundries v. Oak IP, IPR2025‑01129 as § 102/103 prior art against the sibling '880 patent for claims not entitled to the 2002 priority date. (I could not verify the '483 title from retrieved sources — flag before use.)
• US 6,833,556 (Grupp & Connelly, IGFET with passivated Schottky barriers) — related family patent specifically cross-referenced by the '542.

C. Family's own contemporaneous statements of the art (in related WO 2004/015782, retrieved):

• Welch, U.S. Patent 5,663,584 — Schottky-barrier MOSFET systems, disclosed as "metal or metal silicide" source/drain with no interface treatment/interface dielectric.

D. Same-field publications located in related-art search-report excerpts (use with caution — provenance is a European search report, not the '542 file):

• Hara et al., "Pinning-controlled metal/semiconductor interfaces", SPIE Proc. 2779 (1996), pp. 802–806.
• Teraji et al., "Ohmic contacts to n-type 6H-SiC without post-annealing", MRS Symp. Proc. (1996), pp. 149–154.
• Narayan, "Tuning of the Schottky barrier height using bi-metallic layered structures," Appl. Phys. Lett. 59(20), 2541 (1991).
• Adegbo…ga et al., "Schottky contact barrier height enhancement on p-type silicon by wet chemical etching," Appl. Phys. A 48(4), 391–395 (1989).

3. Level of ordinary skill

A POSITA here would hold an M.S./Ph.D. in EE, applied physics, or materials science with ~2–5 years in semiconductor process/device work, familiar with Schottky-barrier physics, MIGS, surface passivation (H/O/N/F termination of Si), thin-dielectric tunneling, and TLM/contact-resistivity measurement. The PTAB's own framework in these IPRs used comparable skill levels dated to the relevant priority date (2002 for the broad claims; 2011/2016 for the later-added features, per the '395 record).

4. Grounds of rejection

Ground I — § 103 over US 7,084,423 (or US 7,176,483) for claims not entitled to the 2002 priority date

This is the strongest and best-documented ground. The Board (as characterized in the GF IPR2025‑01129 petition, citing the Board's ruling in IPR2020‑01206) held that "specific contact resistivity … less than 1 Ω-μm²" and the "oxide of titanium" genus lack written-description/enablement support in the 2002 ancestor applications, so those claims get effective filing dates of 2011/2016 rather than 2002‑08‑12. Once that happens:

• US 7,084,423 issued long before the 2015 grace-period cutoff and is therefore § 102(a)(1) prior art (the § 102(b)(1)(A) grace-period exception cannot reach it, and the § 102(b)(2)(C) common-ownership exception applies only to § 102(a)(2) art — not to an issued patent under § 102(a)(1)).
• Its disclosure is the same text the '542 specification incorporates by reference, so it discloses F1–F4, F6–F7 outright.
• Any residual difference (e.g., a claim reciting "oxide of titanium" or a specific Ω-μm² bound) is supplied by Sze § 3.5 / Rhoderick ch. 3 (specific contact resistance of MIS/tunnel contacts; metal-oxide interlayers on Si) and by the Narayan (1991) and Adegbo…ga (1989) papers on deliberately inserting interlayers/surface treatments to alter barrier height.
• Motivation: the same problem (unpinning the Fermi level to tune barrier height) is stated in both the primary reference and the '542 itself; no change in principle of operation; the secondary references teach the very interlayer material and the very measurement metric.

Note this ground is largely anticipatory in substance and therefore a fortiori obvious: "discovering the mechanism or an additional advantage of a structure already disclosed does not confer patentability" (MPEP 2145; Titanium Metals v. Banner line of authority on the inseparability of structure and properties).

Ground II — § 103 over Tersoff (1984) in view of Hara (1996) / Teraji (1996), further in view of Sze (1981) or Rhoderick

For the broad, 2002-priority claims (F1–F5), this is the cleanest three-reference combination:

1. Tersoff supplies (i) the recognition that the Fermi level is pinned near a gap center by MIGS and (ii) the explicit physical insight that the metal wavefunction decays with distance into the semiconductor — i.e., that moving the metal farther away reduces MIGS. Tersoff is cited on the face of the patent as the state of the art.
2. Hara et al. ("Pinning-controlled metal/semiconductor interfaces") supplies F2: interposing a thin interfacial layer between metal and Si to control the pinning — i.e., depinning as a stated objective.
3. Teraji et al. supplies the SiC variant (F1 for SiC) and the result of an interfacial layer yielding ohmic (low-resistance, current-carrying) contacts without post-annealing — i.e., F4.
4. Sze (1981) and Rhoderick supply the remaining numeric/functional limitations: specific contact resistance as a measured, optimized quantity for MIS tunnel contacts; the known exponential dependence of tunnel current on interlayer thickness; and the known contact-resistance values for heavy doping/tunnel contacts.

Motivation to combine (KSR): (a) Tersoff and Hara address the same problem and the same field (controlling Schottky-barrier height); (b) the modification is a mere rearrangement of known elements with a predictable result — the prior art already taught that the interposition of a dielectric changes the barrier, and Tersoff supplies the reason why (MIGS decay length); (c) there was a known design incentive and a finite number of identified solutions: passivate the surface (H, F, N, O) and/or insert a thin film of one of a handful of dielectrics; (d) the patent itself characterizes the outcome as a trade-off between two known competing mechanisms — MIGS suppression vs. tunneling resistance — which is the paradigm of "obvious to try"/routine optimization.

Ground III — § 103 over the Si-nitridation/oxidation passivation art in view of thin-tunnel-dielectric contact art

For claims reciting the fabrication routes (F7) and the ≤2500/≤1000/≤100/≤50 Ω-μm² bounds (F5):

• The passivation half (F3, F6, F7) is admitted prior art in the '542 itself: the specification states that "a common processing operation performed during semiconductor device fabrication is silicon surface passivation," and that Rapid Thermal Nitridation (RTN) and NH₃/N₂ nitridation of Si are conventional — the '542's novelty is allegedly only in using lower temperature (300–750 °C) and shorter/pulsed exposures. Sze and Rhoderick describe the well-known practice of terminating Si dangling bonds with O, N, H, F, and of measuring surface-state densities.
• The separation-layer/tunnel-barrier half (F2, F5) is likewise conventional in MIS tunnel contacts and in the high-k metal-oxide (including TiO₂≈<1 eV barrier, discussed in the '542 itself) contact literature.

Motivation: Both halves address the two independent pinning mechanisms the patent itself identifies (dangling-bond surface states and MIGS). Combining a known passivation step with a known thin dielectric spacer, both of whose thicknesses are known to be tunable, yields nothing more than the predictable aggregate of their known properties (KSR rationale: "predictable result of combining known elements"). The recited resistance values are result-effective-variable optimization — the specification itself teaches that there is a minimum in the resistance-vs-thickness curve, with no allegation of criticality or an unexpected jump at any of the recited bounds (compare In re Aller; MPEP 2144.05).

Ground IV — § 103 over Welch US 5,663,584 in view of Hara/Tersoff

Welch provides the Schottky-barrier-MOSFET/diode device context (metal source/drain directly on a semiconductor channel), and the patent's own related application criticizes Welch precisely for the absence of an interface dielectric. Supplying a known thin passivating interlayer to Welch's structure to eliminate the admitted problem (uncontrolled, pinned barrier height) is an obvious improvement of a prior-art device in accordance with the prior art's own teaching (In re Sneed; KSR).

5. Why the "depinning" language will not save the claims

• F3 is a functional/result limitation. A structure that is otherwise identical to the prior art is not patentably distinct because it is now "configured to" achieve a result the prior-art structure also achieved, possibly unnoticed. In re Schreiber; MPEP 2114.
• A newly discovered mechanism of an old structure does not create patentability — the '542's contribution is essentially an explanation (MIGS + tunneling trade-off) of a structure the art already taught (metal / thin interlayer / Si). See MPEP 2145 (claims directed to a result) and In re Papesch-line reasoning.
• The numeric limits are a continuous range with no criticality shown — the range 2500 → 1 Ω-μm² spans three orders of magnitude, itself evidence that no sharp threshold was discovered (cf. In re Woodruff, In re Peterson on broad ranges).

6. Counterarguments and secondary considerations to weigh

• Teaching away / criticality: The patent could argue that the art taught away from thin interlayers (SiO₂ "poses a significant barrier to current flow," and SiO₂ "grows very rapidly" so thin layers are hard to control). Rebuttal: the '542 itself acknowledges the growth-control problem is solved by temperature/partial-pressure control — a conventional process-optimization disclosure (Aller) — and the art (Sze, Rhoderick, Narayan) already taught deliberately thin interlayers for barrier engineering.
• Unexpected results: If Patent Owner has data showing a non-monotonic minimum at a specific thickness/material outside routine optimization, that would be the plausible path to non-obviousness. The '542 as supplied shows a schematic FIG. 8 curve but no comparative data or critical-value teaching.
• Secondary considerations (nexus required): The family was asserted in the Eastern District of Texas (Acorn v. Samsung, complaint filed 2019‑10‑23) and Acorn v. GlobalFoundries (2025), and Darts-IP flags first-worldwide-family litigation. Any commercial success, licensing, or industry-acclaim evidence would need a nexus to the claimed interface-layer structure, which — given that the structural elements were known — would be difficult.
• Priority/§ 103 interplay caution: Ground I depends entirely on the priority-date finding. If the challenged claims are entitled to 2002‑08‑12, the family patents are disqualified as prior art and the case rests on Grounds II–IV, where the record (Tersoff + Hara/Teraji + Sze/Rhoderick) is favorable but less airtight.

7. Bottom line

Subject to the verification caveats in § 0, US 9,812,542 is vulnerable under § 103 on at least three independent theories:

1. Self-collision (strongest): any claim with an effective filing date after ~2015 is anticipated/obvious over the family's own earlier-issued US 7,084,423 (and US 7,176,483 / 7,462,860 / 7,884,003), optionally with Sze/Rhoderick for the Ω-μm² and oxide-of-titanium features;
2. Tersoff + Hara + Teraji + Sze/Rhoderick for the broad claims, with KSR rationales of same-field/same-problem, known MIGS decay physics, a finite set of known passivation/interlayer materials, and routine optimization of layer thickness against contact resistance;
3. Admitted-prior-art passivation + known thin tunnel-dielectric contact art for the process-route and resistance-range claims.

The most contestable elements are (i) the exact claim text, which I could not retrieve, and (ii) whether the Board's priority ruling for the "less than 1 Ω-μm²" and "oxide of titanium" limitations (IPR2020‑01206, as characterized in IPR2025‑01129) applies identically to the '542's claim set — both should be confirmed against the '542 file wrapper before filing anything.

Sources

• US 9,812,542 B2 full text (authoritative): https://patents.google.com/patent/[US9812542B2](/patent/US9812542B2)/en
• Sibling US 10,090,395 (same spec/claim families): https://patents.justia.com/patent/[10090395](/patent/10090395)
• IPR2025‑01129 Petition (GlobalFoundries v. Oak IP, US 10,937,880) — priority/§ 102(a)(1) treatment of Grupp '483 and the Board's IPR2020‑01206 ruling: https://ai-lab.exparte.com/documents/ptab/ptacts-uspto/[1558034](/patent/1558034)/CFUd5VwssQlZ0HkCQaT563n3kVoBFAfqA5RC-4QQRy1D7EnxpJNw8Wo/2224244048/IPR2025-01129_doc_1_exparte.pdf
• Samsung IPR declaration citing Rhoderick (Ex. 1023) and priority breakdown for the '395 patent: https://ptacts.uspto.gov/ptacts/public-informations/petitions/[1557765](/patent/1557765)/download-documents?artifactId=wECtF2UP5TH6N6sRF3_pkW1rI3DxYuf5pTCYx7V--vuNvk8LkhojZxg
• US 7,884,003 B2 (family member, same title): https://patentimages.storage.googleapis.com/f8/24/d2/b62c1a63059a48/US7884003.pdf
• WO 2004/015782 A1 (Acorn; identifies Welch US 5,663,584): https://patentimages.storage.googleapis.com/18/05/1a/605ddf45b04028/WO2004015782A1.pdf
• IPR2020‑01282 (Samsung v. Acorn Semi, US 7,884,003 Exhibit 1109): https://www.docketalarm.com/cases/PTAB/IPR2020-01282/Samsung_Electronics_Co._Ltd._v._Acorn_Semi_LLC/docs/07-13-2020-Petitioner/Exhibit-1109-Ex_1109.pdf