US 10286305

I'll run targeted searches for the specific number before summarizing.

Search result first (per your instruction)

No CAFC 2026 docket names US 10,286,305. My targeted searches for the literal string 10286305 returned only (a) the patent's own pages on Google Patents, Unified Patents, uspto.report, FreePatentsOnline, and (b) an unrelated citation of "10286305" inside the reference list of US 12,194,375 (Lyden, "Game controller"). The 2026 Federal Circuit activity in this family is captioned to a different patent:

• Ironburg Inventions Ltd. v. Valve Corp., No. 2024-2088 (Fed. Cir. June 18, 2026) — Hughes, J., joined by Chen, J.; Stark, J., concurring. This is the § 315(e)(2) estoppel reversal on the '525 patent (Kotkin / Willner-Koji-Raymond grounds), consistent with the litigation section already generated. It does not mention or assert US 10,286,305.

I could not query PACER/PTAB E2E directly from this pass, so this is a negative finding on the sources I could reach — same residual caveat already flagged in the litigation section. I am not asserting that no such docket exists; I am stating that nothing I retrieved ties the '305 to any 2026 (or earlier) appellate docket.

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Concise summary — US 10,286,305 B2

Bibliographic

Bibliographic discrepancy — flagged, not reconciled (per your rule): Unified Patents' portal page for the same literal patent number lists priority 2011-06-16, application date 2015-06-29, grant date 2019-05-13, expiration 2031-06-16. Google Patents lists 2011-06-17 / 2015-06-30 / 2019-05-14 / 2031-06-17. I am reporting both literally rather than harmonizing them; the one-day offset is consistent with a time-zone/formatting artifact across databases but I have no authoritative source confirming that.

Abstract (verbatim)

"An improved controller for a game console that is intended to be held by a user in both hands in the same manner as a conventional controller, which has controls on the front operable by the thumbs, and has two additional controls located on the back in positions to be operated by the middle fingers of a user."

Plain-language overview of each independent claim

Claim 1 — "two back paddles, each anchored to the back where the grip meets the recessed mid-back."

1. The shell. A game-controller outer case with a front and a back; a top edge and a bottom edge; a first handle at one side edge and a second handle at the opposite side edge. The back has a recessed portion — a medial area that is indented toward the front relative to the two handles.
2. Two back controls. A first and second back control, each on the back of the case, each comprising an elongate member (a long, thin lever/paddle).
3. Placement. Each elongate member is positioned "at or adjacent a midpoint" of a transition edge — i.e., the boundary line on the back where each protruding handle meets the recessed medial portion.
4. Mounting. Each elongate member is "rigidly connected" to the back by its own rigid connection, where that connection is functionally defined: it applies a moment to the member when a force is applied to the member's free end, thereby restricting rotation of the member.

In plain terms: two long paddles on the back of the controller, one sitting along each seam where the left/right hand-grip transitions into the sunken middle of the back, each firmly fixed (not hinged) so that pressing its free end creates a bending moment at the anchor rather than letting the paddle pivot.

Claim 10 — the same controller, with the transition edges themselves recited as structure.

Claim 10 covers substantially the same subject matter as claim 1, but it moves the "transition edge" limitations up into the case recitation (the back comprises a recessed portion plus an explicit first transition edge between the first handle and the recess and a second transition edge between the second handle and the recess), and then places the elongate members at/adjacent the midpoint of those transition edges. It carries the identical rigid-connection / applies-a-moment / restricts-rotation limitation. The practical difference from claim 1 is claim scope/drafting: in claim 1 the transition edge is referenced functionally as a location on the back; in claim 10 it is a recited structural element of the case.

Claim 20 — one back control spanning both transition edges.

Claim 20 covers a controller with:

1. the same outer case (front/back, top/bottom edges, two handles, recessed back portion, first and second transition edges); and
2. at least one back control at least partially in the recessed portion, having a first outer edge and a second outer edge,
   • where a point on the first outer edge sits at/adjacent the midpoint of the first transition edge, and
   • a point on the second outer edge sits at/adjacent the midpoint of the second transition edge;
3. and the back control is rigidly connected to the outside surface of the back by a rigid connection that applies a moment to the control when force is applied to its free end, restricting rotation.

In plain terms: instead of two separate paddles, a single back control is claimed, and the claim keys both of its side edges to the two transition-edge midpoints — plus the same rigid-moment mounting requirement.

Reading note (consistent with the earlier sections)

The independent claims are structural/positional, not material- or resilience-based. They require (i) a recessed back relative to the handles, (ii) midpoint placement of back controls along the handle-to-recess transition edges, and (iii) a rigid connection that resists rotation by applying a moment. This is notably different claim language from the '525 parent's "inherently resilient and flexible"/"substantially the full distance" phrasing, and from the specification's own description of the paddles as thin, flexible, inherently resilient members that bend and rebound — the tension the prior sections identified as a potential § 112 written-description/enablement issue. I flag that tension here as a cross-reference, not as a new finding.

Stated uncertainties

• Caveat / CAFC check: I found no 2026 Federal Circuit docket for the '305; the only 2026 family opinion I located is Ironburg v. Valve, No. 2024-2088 (June 18, 2026), on the '525. Confirm at PTAB E2E / PACER if this summary is being used for a filing.
• Date fields: Google Patents and Unified Patents disagree by one day on priority, filing, grant, and expiration dates. Reported literally above; not harmonized.
• Current date mismatch: the task header states April 26, 2026, while the authoritative patent text and retrieved sources include a June 18, 2026 opinion and a 2026-07-03 source. Following the instruction to prefer retrieved results, I have treated the June 2026 items as current.
• Everything above is drawn from the authoritative patent text supplied in this prompt and the retrieved USPTO/Google Patents/Unified Patents/uspto.report records; I did not rely on training-data recollections to fill any gap.

I'll search specifically for litigation naming US 10,286,305. Let me run several targeted queries.

Let me check the Unified Patents litigation portal and other case databases directly.

Let me run a few final targeted checks on case databases and the Ironburg litigation docket list.

Litigation Involving US 10,286,305 — Search Findings

Bottom line

No litigation is known that specifically names U.S. Patent No. 10,286,305. Across the sources I searched — the Unified Patents patent portal entry for US-10286305-B2, Google Patents' litigation flag and "Cited By"/"Family" records, Justia/uspto.report entries, CourtListener RECAP, Federal Circuit opinions, PTAB records, and general reports on Ironburg's enforcement campaign — no complaint, docket, or case number identifies the '305 patent as an asserted patent. I cannot provide a plaintiff/defendant/jurisdiction/case-number table for the '305 because no such case appears in the record.

Important non-correction (strict-identifier rule): My first search surfaced Citadel Securities LLC v. HFT Solutions, LLC (N.D. Ill., filed Dec. 2024), asserting U.S. Patent Nos. 11,128,305, 10,931,286, and 11,575,381. "11,128,305" is not "10,286,305." These are different patents, different owners (HFT Solutions, not Ironburg), and a different field (FPGA/phase-locked-loop technology). I am flagging it only so it is not mistaken for the '305. Likewise, US 10,286,307 (Microsoft, "Game controller with removable faceted finger pad") is a different patent in the same numbering neighborhood and is not the '305.

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Search trail (what was checked, and what it returned)

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Related Ironburg-family litigation — NOT cases on the '305

The following are the known suits in the same corporate family and patent chain. None asserts US 10,286,305. I list them so the distinction is explicit, and because they are the cases an adversary or a demand-letter recipient will most often confuse with the '305.

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Why the '305 likely has no litigation — and the caveat on that conclusion

Two structural facts explain the absence:

1. Timing. The '305 issued 2019-05-14, after the 2015–2019 assertion wave in this family (the Valve suit was filed in 2015 and tried in 2021). Ironburg asserted the '525 and '770 — the earlier-issued members of the same 2011 chain — rather than waiting for the '305.
2. Terminal-disclaimer-limited term. Google Patents lists an anticipated expiration of 2031-06-17, which is earlier than 20 years from the 2015-06-30 filing date and implies the '305 is terminally disclaimed to the 2011-06-17 chain. That limits its assertion runway relative to siblings.

Caveats I must state honestly:

• My conclusion is a negative finding. It rests on the sources above; it is not proof that no unindexed, sealed, or very recent action exists. A PACER/Justia docket-name query for "10,286,305" and a check of Ironburg's full case list (and of any complaints filed after mid-2026) would be the definitive step.
• The Google Patents "Family has litigation" flag and the Darts-ip family link are family-level, not patent-level, evidence. They should not be cited as proof that the '305 itself has been litigated.
• Date discrepancy (carried forward): the prompt states today is April 26, 2026, but the retrieved materials include a June 18, 2026 precedential Federal Circuit opinion and later-2026 commentary. Per the instruction to prefer retrieved results over conflicting assumptions, I report those items as current — but it also means my "no litigation" finding could not have captured anything filed between April and the present.

One additional discrepancy to note (consistent with the earlier sections): Unified Patents' portal lists this patent's priority date as 2011-06-16 and application date 2015-06-29, whereas the authoritative front page of US 10,286,305 gives 2011-06-17 and 2015-06-30. I treat the patent's own front page as controlling, but flag that the '305's date metadata is inconsistent across databases — worth verifying before relying on any date in a filing.

I'll start by verifying the PTAB record via web search, since the ODP block reports no AIA trial proceedings.

The ODP block reports no AIA trials. Let me verify against the sibling-patent record and check specifically for any petition naming the '305 patent.

Let me run a final targeted check for any post-2019 petitions against the '305 or its siblings.

Proceedings overview

Total AIA trial proceedings naming US 10,286,305: zero. The structured "PTAB proceedings on file" block reports the USPTO Open Data Portal returns no AIA trial proceedings for this patent, and my independent web checks (PTAB E2E petition pages, Ironburg v. Valve/CMG coverage, Federal Circuit reporting, and the patent's own citation record) surfaced no IPR, PGR, or CBM petition naming US 10,286,305 — no institution decisions, no FWDs, no terminations, no appeals. There is therefore no claims-invalidated / claims-sustained / settled / institution-denied breakdown to report: it is 0-0-0-0-0.

Bottom-line defensive posture: the '305 is untested at the PTAB, not hardened. Because no IPR on this patent has ever reached a final written decision, no § 315(e) estoppel attaches to anyone as to the '305's claims, and the full universe of prior art remains available to a defendant — including the art that Ironburg has already litigated to FWD on its sibling patents. Do not let an opponent borrow the '525/'770/'688/'229 outcomes as if they were adjudications of the '305's claims; the claim language is materially different (see the claim-shape note below).

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Per-proceeding detail

There are no proceedings to itemize. I am not going to populate the {PROCEEDING_NUMBER} template with proceedings that do not exist. What follows is (a) the verification trail, (b) the sibling-patent PTAB history that a defendant will be handed as leverage, and (c) why it does and does not transfer.

Verification trail

• ODP structured block (provided in this prompt): "The USPTO ODP API returns no AIA trial proceedings for this patent as of the most recent ingest." → canonical answer: no activity.
• Primary-source check pending: confirm at PTAB E2E (https://ptacts.uspto.gov/ptacts/) by searching the patent number 10286305 and application 14/754,789. Web search is not a substitute for the E2E docket for a zero-result finding; treat this as the one open verification step.
• Why a "no results" finding is plausible rather than a search failure: the '305 issued 2019-05-14, i.e. after the 2016–2018 petition wave. The '305's priority chain runs to 2011-06-17, which makes it a pre-AIA patent — so no PGR (unavailable for pre-2013-03-16 priority) and no CBM (game controllers are not covered business methods, and the CBM program has sunset). IPR is the only AIA trial vehicle that was ever available against it, and nobody used it.
• Litigation posture: Google Patents flags "Family has litigation." The heavy Ironburg enforcement activity I could confirm (Valve, W.D. Wash. 2:17-cv-01182-TSZ; and the CMG third-party IPR) centered on the '525/'770 and the separate '688/'229 families. I found no confirmation that the '305 itself has been asserted; if you have a demand letter citing the '305, ask the sender for the case number — the absence of a prior IPR is a meaningful tell about how assertable they believe it is.

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Adjacent PTAB activity — sibling patents (these are NOT proceedings on the '305)

Everything below concerns different patents. It is included because it is the leverage an adversary will wave at you, and because it tells you how the art has already been tested.

Federal Circuit estoppel saga on the '525 (not the '305), which drives all current § 315(e)(2) law in this family:

• Ironburg Inventions Ltd. v. Valve Corp., Nos. 2021-2296, 2021-2297, 2022-1070, 64 F.4th 1274 (Fed. Cir. 2023-04-03) — adopted the "skilled searcher" standard; held the patent owner bears the burden of proving estoppel by a preponderance; affirmed estoppel as to non-instituted grounds.
• Ironburg Inventions Ltd. v. Valve Corp., No. 2024-2088 (Fed. Cir. 2026-06-18), 178 F.4th 1328 — reversed estoppel again. A classification search returning 26,333 references does not prove discoverability: "something more is required for estoppel when a classification search alone returns an unreviewable number of search results." Separately, Ironburg's retroactive 2023 searches were tainted by hindsight (undated forward/backward citation queries pulling in post-petition art). Remanded so Valve may assert both the Kotkin ground and the Willner-Koji-Raymond ground at trial. Judge Stark concurred, splitting findability from discoverability.

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Strategic summary

Claim status on the '305. No claim of US 10,286,305 has been canceled, sustained, or even tested at the PTAB. All 21 claims (1–21) are UNTESTED. The patent is active, large-entity, 4th-year maintenance fee paid 2022-11-28 (with a late-payment surcharge), and Google Patents lists an anticipated expiration of 2031-06-17 — which is earlier than 20 years from the 2015-06-30 filing date and therefore implies a terminal disclaimer tying term to the 2011-06-17 chain. Confirm that in the file history: it controls how much runway an assertion actually has (roughly 4.7 years from today).

Why sibling results don't transfer. The '305 is a continuation of US 14/141,840 (which issued as the '770) and shares the 2011 specification, but its claims are drafted around a different invention: a back case with a recessed portion relative to the handles, first/second transition edges between handle and recess, elongate members positioned "at or adjacent a midpoint" of those transition edges, and a "rigid connection" configured to apply a moment and "restrict rotation" of the member. Contrast the '525 claim 1 language that died at the PTAB — an elongate member "extend[ing] substantially the full distance between the top edge and the bottom edge" that is "inherently resilient and flexible." The art that carried the day on the siblings (Tosaki; Enright; Uy; Burns; LaCelle; Kotkin; Willner/Koji/Raymond) was aimed at the resilient-flexible-elongate-member genus. It has not been applied to the '305's transition-edge-midpoint + rigid-connection + moment limitations. Those limitations also invite a § 112 attack in litigation: the '305 specification describes paddles that are thin, flexible, inherently resilient, bend and return — it is not obvious that it describes or enables a connection that rigidly restricts rotation and applies a moment. That is a written-description/enablement theory the Board never reached on any sibling.

Estoppel landscape: essentially clean for a would-be IPR petitioner on the '305. Section § 315(e)(2) estoppel runs per patent, and it only attaches after an FWD on that patent. There has been no FWD on the '305, so no petitioner or privy is estopped from raising any ground against it. Conversely, if you are a defendant being asserted on the '305: (i) the § 315(b) one-year clock runs from service of the complaint on you, and the PTAB has no proceeding to join; (ii) the sibling FWDs create no issue preclusion against the '305's distinct claims; and (iii) you can use the Ironburg II framework affirmatively — if Ironburg later argues you are estopped, it carries the burden of proving a skilled searcher would have found your grounds, and Ironburg II just made that burden harder.

Pattern signals. No defensive aggregator (e.g., Unified Patents) appears in this patent's chain — Unified's portal carries a '305 profile page, but I found no Unified-filed petition. The repeat petitioners in this portfolio are Valve (four-plus IPRs across '525/'770/'688/'229) and Collective Minds (one IPR, settled out). Ironburg is a serial, aggressive PTAB appellant — three Federal Circuit trips on the '525 estoppel issue alone, and it litigated the '688/'229 remands rather than settling. Expect Ironburg to fight an IPR on the '305 hard, but note it has never had to defend this claim set.

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Recommended next steps

1. Close the one verification gap. Run PTAB E2E (https://ptacts.uspto.gov/ptacts/) on patent number 10286305 and application 14/754,789, and on the '305's siblings 9878238 / 11278797 / 11806613 / 12318686. If E2E returns nothing (as the ODP block predicts), record the date of the search — a zero-result E2E docket for an 11-year-old, family-litigated controller patent is itself a signal that the '305 is treated as the narrow fallback rather than the primary weapon.
2. Do not answer a demand letter that cites canceled claims. If the letter cites the '525 claims 1, 6, 13, 14, 16, 17, 19 or 20, those were canceled in IPR2016-00948 (FWD Sept. 2017; aff'd 773 F. App'x 622) — that is sanction-bait. If it cites the '770, remember the surviving claims fell to summary judgment of non-infringement. But if it cites the '305, none of that helps you directly — you are facing an untested claim set.
3. If you want to file, move on the § 315(b) clock. There is no pending proceeding to join and no estoppel bar, so a clean IPR is available. Build the petition around the '305's distinct limitations — the midpoint-of-transition-edge placement and the "rigid connection ... apply a moment ... restrict rotation" element — not around the resilient-flexible-elongate-member art that the '525/'688/'229 panels already exhausted. Use the same reference families as a starting point (Uy, Burns, LaCelle, Kotkin, Willner/Koji/Raymond) but chart them against the '305's actual claim language, and document your search diligence carefully: Ironburg II shows Ironburg will attack your search methodology to manufacture estoppel, and a hindsight-tainted search record is now a proven liability.
4. Preserve the § 112 theory for litigation. Because the '305 specification teaches a thin, flexible, inherently resilient paddle that bends and rebounds, while claim 1 requires a rigid connection that restricts rotation and applies a moment, a written-description/enablement challenge is worth developing through an expert now — it is the one invalidity theory the PTAB has never had a chance to reject on this claim set.
5. Track the Ironburg II remand. The W.D. Wash. case (No. 2:17-cv-01182-TSZ; see the RECAP file at https://storage.courtlistener.com/recap/gov.uscourts.wawd.[248491](/patent/248491)/gov.uscourts.wawd.248491.475.0.pdf) is back for a third round on estoppel with Valve allowed to assert Kotkin and Willner/Koji/Raymond. Those references will finally get a jury (or bench) test in that court, and any resulting validity findings will be the best available preview of how Ironburg's paddle claims fare on the merits.

One honest limitation: my "zero proceedings" conclusion rests on the ODP structured block plus web verification. It is a negative finding, so the residual risk is a very recent petition that neither ODP nor my searches have indexed. The E2E lookup in step 1 is the only thing that closes that gap, and I would run it before relying on the zero count in a brief.

I'll verify the ownership and litigation context with targeted searches before finalizing.

Let me check the assertion history and any NPE-list presence for the owner.

Ownership & Assignment Reconstruction — US 10,286,305 B2

Patent: US 10,286,305 B2 "Controller for video game console" — Appl. No. 14/754,789, filed 2015-06-30 as a continuation of 14/141,840 (US 9,089,770) → 13/162,727 (US 8,641,525), earliest priority 2011-06-17. Granted 2019-05-14; status Active; anticipated expiration 2031-06-17.

Note on sourcing: The reel/frame numbers and conveyance types below are taken from the Google Patents legal-events export for this patent (which mirrors the USPTO Assignment Center records). The correspondent-of-record field is not exposed in that export, so signal #3 below is reported as indeterminate rather than guessed. Verify at USPTO Assignment Center by patent number 10286305 or application 14/754,789.

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Inventors

Unusual pattern — flagged: The family's priority application was filed 2011-06-17 and this continuation on 2015-06-30, yet the inventors' assignment to Ironburg was not signed until 2016-05-05/05-06. Court filings in Ironburg v. Valve (W.D. Wash. 2:17-cv-01182, Dkt. 408) describe a "Burgess Buyout Analysis" prepared by Scuf Gaming's finance team "in late 2015 and early 2016" for the assets "acquired by Scuf Gaming from Simon Burgess in connection with his buyout from the Scuf Gaming companies, including his interest in Ironburg and the '525 Patent." So one of the two named inventors exited the inventing company roughly 10–11 months after this application was filed, and the confirmatory paper assignment tracks that exit almost to the day. This is a founder-departure/equity-cleanup event — here it preceded a sale to Corsair (Dec 2019), not a fire-sale, but it is the same "inventor exits shortly after filing" footprint that often precedes a portfolio transaction.

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Original assignee

Ironburg Inventions Ltd. — UK private company (recorded address: Somerset, later 10 Market Place, Wincanton, Somerset BA9 9LP per EP register entries). It is the patent-holding/licensing arm of Scuf Gaming, not a manufacturer.

• Product embodying the claims: Not by Ironburg itself. The practicing affiliate is Scuf Gaming International, LLC (Atlanta, GA) — described in the 2013 Playrapid/BURN complaint as "the company through which Ironburg conducts business in the United States," and in the 2016 Collective Minds action as the entity through which Ironburg "manufactures and sells custom video game equipment and accessories." The Federal Circuit's June 2026 opinion describes the appellee plainly as "a patent-holding and licensing company" (Vitallaw summary). Scuf itself sells back-paddle controllers, and Ironburg licensed the paddle technology to Microsoft (~$6M deal referenced in the Valve damages record) and worked with Sony on the 2018 DualShock 4 back-button attachment.
• Primary line of business: IP holding, licensing, and enforcement of the Scuf back-paddle/controller patent portfolio (Scuf claimed 103 granted + 55 pending patents in Dec 2019).
• Current status: Operating as a subsidiary of Corsair Gaming, Inc. (NASDAQ: CRSR). Corsair agreed on 2019-12-16 and closed on 2019-12-19 the acquisition of SCUF Holdings, Inc. and its subsidiaries (Corsair 10-K: results consolidated from December 19, 2019). No assignment of US 10,286,305 to Corsair or SCUF Holdings appears in the record — consistent with a share purchase, under which Ironburg Inventions Ltd. remains the owner of record.

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Assignment timeline

Four recorded events. All four are either inventor-formality, securitization, or release — there is no recorded transfer of this patent to any third-party acquirer or shell entity.

• 2016-05-05 to 2016-05-06 (executed) / recorded 2016-05-07 — Reel 038640/0148

  • Conveyance: Assignment (assignment of assignors' interest)
  • Assignor: BURGESS, SIMON and IRONMONGER, DUNCAN
  • Assignee: IRONBURG INVENTIONS, LTD. (United Kingdom)
  • Correspondent: Not exposed in the retrieved record — verify at Assignment Center.
  • Context: Confirmatory inventor-to-company assignment, executed ~11 months after the 2015-06-30 filing and contemporaneous with Simon Burgess's buyout from the Scuf/Ironburg companies.

• 2016-12-07 (executed) / recorded 2016-12-09 — Reel 040878/0527

  • Conveyance: Security Interest ("Security Agreement" per the record description)
  • Assignor: IRONBURG INVENTIONS LIMITED
  • Assignee / secured party: TRIANGLE CAPITAL CORPORATION (North Carolina)
  • Correspondent: Not exposed in the retrieved record.
  • Context: Securitization — collateral pledge of the patent portfolio under a venture-debt facility.

• 2016-12-07 (executed) / recorded 2016-12-12 — Reel 040884/0057

  • Conveyance: Security Interest
  • Assignor: IRONBURG INVENTIONS LIMITED
  • Assignee / secured party: TRIANGLE CAPITAL CORPORATION, AS AGENT
  • Correspondent: Not exposed in the retrieved record.
  • Context: Securitization (duplicate/parallel filing) — same execution date as reel 040878/0527, filed three days later in the agent capacity, a standard belt-and-suspenders perfection practice for a single loan, not a cascading multi-party transfer.

• 2019-12-19 (effective) / recorded 2020-01-13 — Reel 051569/0397

  • Conveyance: Release by Secured Party
  • Assignor / releasing party: BSP AGENCY LLC (successor secured-party agent)
  • Assignee / released party: IRONBURG INVENTIONS LIMITED
  • Correspondent: Not exposed in the retrieved record.
  • Context: Lien release on debt payoff — effective the same day Corsair's acquisition of SCUF Holdings closed, i.e., the loan was repaid/refinanced as part of the sale. This is the last recorded assignment; Ironburg has held clean title since.

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Timeline diagram

timeline
    title Ownership of US 10286305
    2011 : Priority application filed
    2015 : Continuation application filed
    2016 : Inventors assign rights to Ironburg
         : Security interest to Triangle Capital
         : Second security interest filing recorded
    2019 : Secured interest released
         : Corsair acquires Scuf Gaming
    2021 : Jury finds Valve infringed sister patent

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NPE / troll-pattern signals

1. Shell-entity transfer — not present. No assignment moves this patent out of the original owner family. Ironburg Inventions Ltd. has been the assignee since the confirmatory assignment at reel 038640/0148, and the only subsequent entries are a security interest (040878/0527; 040884/0057) and its release (051569/0397). Ironburg is admittedly a licensing-only entity — but it is a pre-existing IP affiliate of the practicing manufacturer (Scuf Gaming), not a shell created to receive a transferred patent, and it shares founders with Scuf. No recorded transfer to a new Delaware/Texas LLC, no registered-agent service address on the face of the record.

2. Known asserter in the chain — not present. Ironburg Inventions Ltd. does not appear on the enumerated lists (Acacia, Marathon, Intellectual Ventures, IPNav, Wi-LAN/Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, DGC, Spangenberg entities). It is a repeat plaintiff of the operating-company-with-licensed-competitors type, not an aggregator: Scuf Gaming Int'l/Ironburg v. Playrapid EURL & BURN Controllers (N.D. Ga. 1:13-cv-03224, filed 2013-09-27); Ironburg v. Collective Minds Gaming (N.D. Ga. 1:16-cv-04110, 2016); Ironburg v. Valve (N.D. Ga. → W.D. Wash. 2:17-cv-01182; February 2021 jury verdict of $4,029,533.93 plus a willfulness finding). Its patent assertions are paired with actual licensing revenue and a shipped product, which is the inverse of the aggregator pattern.

3. Repeat correspondent across the chain — unclear / insufficient data. The retrieved records do not expose the correspondent-of-record for any of the four reel/frame entries, so recurrence cannot be tested. This is the one signal I cannot responsibly mark either way; a live Assignment Center lookup (search 10286305 → each reel/frame → "Correspondent") is required. For context, litigation counsel of record for Ironburg in the Valve matter were Dorsey & Whitney LLP (Gregory S. Tamkin) at the Federal Circuit (June 2026, No. 24-2088) and, per contemporaneous reporting, Manatt Phelps at the 2021 trial — but litigation counsel is not the same field as the assignment correspondent and should not be substituted for it.

4. Cascading transfers — not present. Four events across 3.7 years, of which two are the same secured party filing twice on the same execution date (2016-12-07 → reels 040878/0527 and 040884/0057). No chained LLCs, no shared-address assignees, no rapid successive changes of owner.

5. Pre-litigation transfer — not present (and not verifiable as to this patent). The nearest assignment in time is the confirmatory deed at reel 038640/0148 (executed 2016-05-05/06, recorded 2016-05-07), which lands roughly three months before the Collective Minds complaint (2016). However, the '305 patent itself was not the asserted patent in that case — the '525 and '770 patents were — and my searches surfaced no complaint naming US 10,286,305; the family has been litigated through the '525, '688, '229 and '770 patents instead. I could not complete verification of litigation naming this specific patent before running out of search steps, so treat "no suit on '305" as unconfirmed rather than established.

6. Bankruptcy fire-sale — not present. No Chapter 7/11 event for Ironburg or Scuf in the record. The debt against the portfolio was repaid and released (reel 051569/0397, effective 2019-12-19) as part of an acquisition, the opposite of a distressed sale.

7. Privateering — not present. Privateering requires an operating company to transfer patents to an unrelated NPE that then asserts on its behalf. Here the plaintiff and the licensee/manufacturer are affiliates in the same corporate family (Ironburg owns; Scuf has been described in court filings as exclusive licensee and the US operating arm; both now sit under Corsair). This is an ordinary IPCo/OpCo affiliate structure, not a third-party proxy campaign, and Corsair publicly announced the Valve win as "its subsidiaries Scuf Gaming and Ironburg Inventions Ltd."

8. Defensive aggregator — not present. The chain does not terminate at RPX, AST, LOT, Unified Patents, or OIN. It terminates at Ironburg Inventions Ltd., a Corsair subsidiary. (Ironburg has been a target of third-party IPR challenges — Valve's IPR2016-00948 and IPR2017-00858/-01928 on the sibling '688/'229 patents — but that is the inverse relationship.)

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Verdict

Operating-company assertion.

The record shows continuous ownership by the same corporate family from filing to today: inventors Burgess and Ironmonger assigned to Ironburg Inventions, Ltd. (reel 038640/0148, executed 2016-05-05/06), the portfolio was pledged to Triangle Capital Corporation (reels 040878/0527 and 040884/0057, executed 2016-12-07) and released on payoff (051569/0397, effective 2019-12-19) — with no assignment to any acquisitions vehicle, shell LLC, or aggregator at any point. Ironburg is the patent-holding affiliate of Scuf Gaming, whose controllers embody the claimed back-paddle control, and the family has been enforced against genuine competitors (Valve, Collective Minds, Playrapid/BURN) while being licensed to others (Microsoft, ~$6M; Sony collaboration), which is the definition of operating-company assertion rather than NPE conduct. The one honest caveat is that Ironburg itself is a licensing-only entity, and the correspondent-of-record field could not be read from the available record — a live Assignment Center check of the four reel/frame entries is needed to close out signal #3.

Verify: https://assignmentcenter.uspto.gov/ — search patent 10286305, then open reels 038640/0148, 040878/0527, 040884/0057, 051569/0397.

I'll research the specific prior-art references cited for US 10,286,305. Let me run targeted searches to verify citations and dates.

Let me verify additional key cited references and check for any IPR specifically on the '305.

Prior-Art Analysis — US 10,286,305 B2 ("the '305 patent")

Scope note: I searched for and confirmed the record for US 10,286,305 B2 specifically (Burgess et al., "Controller for video game console," assignee Ironburg Inventions Ltd.). I did not substitute similar numbers — e.g., US 10,286,307 B2 (Microsoft, "Game controller with removable faceted finger pad") and the '305's own siblings (US 9,878,238; US 11,278,797; US 11,806,613; US 12,318,686) are distinct documents and are treated as such below.

This section builds on, and does not repeat, the earlier bibliographic/claim summary. It uses the 82-reference patent citation list printed on the face of the '305 patent as the authoritative reference set, cross-checked against the family's IPR record.

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1. Methodology and three controlling caveats

Caveat A — "cited" ≠ "anticipatory." The references on the '305 front page fall into three buckets: (i) examiner-cited art (marked "*" in the printed patent), (ii) applicant/inventor- and third-party-cited art, and (iii) background references cited to show the state of the art (e.g., generic Nintendo/Sony/Sega controllers). Most of the list is § 103 (obviousness) material, not § 102 (anticipation) material. I flag anticipation potential only where a single reference could plausibly disclose every limitation.

Caveat B — priority / effective date governs the § 102 analysis. The '305 claims 2011-06-17 priority as a continuation of the '770/'525 chain. If the added "transition-edge midpoint / rigid-connection" limitations are not entitled to 2011 priority, the effective date slides to the 2015-06-30 filing, which expands the prior-art field (it would sweep in, e.g., the 2013 Razer Sabertooth review and the 2012/2013 GBP/US design filings). Conflict to re-flag (consistent with the earlier summary): Google Patents says 2011-06-17; Unified Patents' portal for US-10286305-B2 says 2011-06-16. I treat 2011-06-17 as controlling.

Caveat C — own-family references are not prior art. US 8,641,525 and US 9,089,770 are the '305's own parents; they cannot be § 102/§ 103 art against it. They appear on the list as related documents, not as references.

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2. TIER 1 — Most relevant references (handheld controller with back/rear finger controls)

These are the references with the most direct bearing on the independent claims (1, 10, 20), because each discloses controls actuated by fingers other than the thumbs, located on the underside/back or side of a handheld controller.

T1.a — US 2010/0298053 A1 — Kotkin / Icontrol Enterprises, LLC

• Full citation: U.S. Patent Application Pub. No. 2010/0298053 A1, "Device for enhancing operation of a game controller and method of using the same," Icontrol Enterprises, LLC (inventor David Kotkin). Pub. Nov. 25, 2010; priority to US provisional 61/179,551 (May 19, 2009). Corresponding PCT: WO 2010/135287 A3.
• Description: An accessory/"skin" for a game controller with at least one actuator cooperating with the controller to add functions controlled by parts of the hand other than the thumbs (e.g., side/tip of index finger) while the thumbs operate other functions. Includes rear/side actuators and lever assemblies.
• § 102 potential: This is the "Kotkin" reference already at issue in the family's § 315(e)(2) estoppel litigation (identified in the earlier summary's item 4(a)). Because it expressly discloses non-thumb-actuated additional controls on a handheld controller, it is the most likely single reference to be asserted against independent claims 1, 10 and 20. However, on the record I have, it does not clearly disclose the claimed elongate member positioned at the midpoint of a handle-to-recess transition edge with a rigid connection applying a moment; it is best characterized as a § 103 primary reference rather than a clean § 102 anticipation. Anticipation potential: claims 1, 10, 20 (weak/arguable — likely needs combination).

T1.b — WO 2008/131249 A1 and US 2008/0261695 A1 — Coe

• Full citation: WO 2008/131249 A1, "Game controller," Adam W. Coe (PCT/US2008/060861), pub. Oct. 30, 2008; U.S. counterpart Pub. No. US 2008/0261695 A1, pub. Oct. 23, 2008; issued as US 8,932,135 B2 (Jan. 13, 2015), filed Feb. 15, 2008.
• Description: A game controller with first and second buttons extending through the upper and lower portions of the housing, in communication with the same control-circuit input — i.e., a lower (back/bottom) button that replicates an upper button so the player need not move the thumb. Expressly contemplates the lower button being pressed by ring/little fingers.
• § 102 potential: Discloses the core inventive concept (back control replicating a front control, operated by non-thumb fingers), but its "lower buttons" are discrete buttons, not elongate members keyed to transition-edge midpoints, and there is no rigid-connection/moment disclosure. Anticipation of independents 1/10/20 is unlikely on its face; it is strong § 103 art. It was a named reference in the family IPR (Enright–Tosaki / Tosaki combinations). Anticipation potential: claims 1, 10, 20 (weak).

T1.c — US 2010/0073283 A1 — Enright

• Full citation: U.S. Pub. No. 2010/0073283 A1, "Controller with user-selectable discrete button emulation," Robert Enright. Filed Sept. 19, 2008; pub. Mar. 25, 2010.
• Description: A controller in which a control with dual functionality / user-selectable emulation lets a player remap or emulate discrete buttons. This is the "Enright" reference that, in view of Tosaki, was used against the '770 patent's claims in IPR2016-00949.
• § 102 potential: Enright's relevance is to function replication/remapping, not to the '305's structural back-paddle geometry. Not an anticipatory reference for claims 1/10/20; relevant to § 103 and to the functional "replicate a front control" description. Anticipation potential: none for the independents.

T1.d — US 7,407,439 B1 — Ochoa

• Full citation: US 7,407,439 B1, "Apparatus and system for reconfigurable two-hand game controllers," Justin J. Ochoa. Filed Dec. 29, 2004; issued Aug. 5, 2008.
• Description: Reconfigurable two-hand game controller with modular/relocatable controls.
• § 102 potential: Relevant background for two-hand controller architecture and relocation of controls; does not disclose rear elongate paddles at handle/recess transition-edge midpoints. § 103 only.

T1.e — US 2006/0040740 A1 and US 7,235,012 B2 — Brain Box Concepts

• Full citation: US 2006/0040740 A1, "Video game controller," Brain Box Concepts, Inc. Pub. Feb. 23, 2006; US 7,235,012 B2, "Video game controller with side or quick look feature," issued June 26, 2007.
• Description: Controller with auxiliary/side actuation features aimed at keeping the thumbs on the sticks.
• § 102 potential: Background/side-actuation art; no rear transition-edge paddle geometry. § 103 only.

T1.f — US 5,923,317 A — Seiler / Thrustmaster

• Full citation: US 5,923,317 A, "Two-handed controller for video games and simulations," Seiler et al. (Thrustmaster, Inc.). Filed June 17, 1997; issued July 13, 1999.
• Description: A two-handed controller with grips/handles and multiple finger-actuated controls.
• § 102 potential: Discloses a two-hand controller with handles and finger-operated controls, but not the claimed rear recess-plus-paddle-at-transition-edge structure. § 103/background.

T1.g — US 5,207,426 A — Inoue / Nintendo

• Full citation: US 5,207,426 A, "Controller for a game machine," Nintendo Co., Ltd. Filed Aug. 9, 1990; issued May 4, 1993.
• Description: Early Nintendo game-machine controller with front controls and grip portions.
• § 102 potential: Establishes the conventional front-control/handle architecture recited in the '305's preamble; cannot anticipate the rear-control limitations. § 103/background.

T1.h — US 4,552,360 A — Bromley / Coleco

• Full citation: US 4,552,360 A, "Video game with control of movement and rate of movement of a plurality of game objects," Coleco Industries, Inc. Filed Sept. 29, 1982; issued Nov. 12, 1985.
• Description: Video-game control with multi-object movement control.
• § 102 potential: Cited for controller/input background; nothing on rear paddles. § 103/background.

T1.i — GB 2 481 633 A — Burgess (same inventor family)

• Full citation: GB 2 481 633 A, "Games console controller with buttons on underside," Simon David Burgess. Filed July 1, 2010; published Jan. 4, 2012.
• Description: A games-console controller with buttons on the underside — i.e., underside finger controls.
• § 102 potential — flag: This is highly on-point thematically (underside/back controls) but carries two complications: (1) it names Simon David Burgess, the '305's own co-inventor, so inventor-disclosure/grace-period and derivation issues arise; and (2) as a foreign (UK) application published Jan. 4, 2012 (after the 2011-06-17 priority date but before the 2015 filing), it functions as prior art only if the '305 claims fall back to a 2015 effective date (or as § 102(a)(1) art against any non-2011-supported claims). If the claims keep 2011 priority, GB 2 481 633 is not § 102(a)/(b) art. It is cited on the face of the parent '525 patent as well. Anticipation potential: claims 1, 10, 20 (only if effective date moves to 2015; otherwise not prior art).

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3. TIER 2 — Other cited patent references (dates and relevance)

Presented as "filed / published"; descriptions are condensed. None of these, standing alone, appears to disclose the full combination of the '305 independents (rear recessed portion + elongate members at handle/recess transition-edge midpoints + rigid connection applying a moment).

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4. TIER 3 — Non-patent literature (strongest § 102(a)(1) candidates)

Of all the cited material, the NPL references are the most dangerous as § 102(a)(1) "printed publication" art because they are product disclosures that predate 2011-06-17 and were already litigated.

1. "Review: Scuf Xbox 360 Controller," by Dave Burns — published Oct. 20, 2010 (archived: web.archive.org/web/20101022215104/http://www.xboxer360.com/features/review-scuf-xbox-360-controller/). This is the central "Burns article." Per the family's own litigation record (Valve Corp. v. Ironburg), it discloses "a controller with 2 paddles to the back of the control pad … made from polycarbonate." § 102(a)(1) potential: claims 1, 10, 20 (and dependents 2–9, 11–21) — the closest thing to an anticipatory printed publication on the back-paddle concept. Whether it discloses the transition-edge-midpoint and rigid-connection/moment limitations is the crux and is not established on the face of the article.
2. "Rapid Fire Mod for Wireless Xbox 360 Controller," xbox-scene.com (2008) and "Rapid Fire Mod … Step by Step" (July 13, 2008) — § 102(a)(1) candidate for controller-modification background; not anticipatory of the rear-paddle geometry.
3. AlphaGrip AG-5 handheld keyboard and mouse, Ryan Paul, Mar. 15, 2006 — § 102(a)(1) candidate for hand-held grip/data-entry; underlies the Alphagrip patents (US 6,512,511; US 6,760,013).
4. Razer Sabertooth Review, Harry Butler, Mar. 11, 2013 — post-dates 2011-06-17; § 102 art only if the claims' effective date moves to 2015-06-30.
5. Coles, Olin, "Thrustmaster Run-N-Drive PC/PS3 Wireless Gamepad," BenchmarkReviews.com (2009) — § 102(a)(1) candidate; generic gamepad.
6. "Xbox 360 Wireless Controller Tour," May 13, 2005 and Xbox 360 Wireless Controller (GameStop listing) — § 102(a)(1) — baseline conventional controller (the '305's own FIG. 1).
7. Nintendo Game Boy Advance, model AGB-001 — § 102(a)(1) — handheld background.
8. "Dark Watcher," History of the Game Controller (2008) — § 102(a)(1) — background.
9. IPR/PTAB and prosecution-history items (Decision on Petition re US 8,614,525; Patent Owner Preliminary Response in IPR2018-00354 (Mar. 28, 2018); File Histories of US 13/162,727, US 9,289,688, US 9,352,229; Search & Examination Report GB1011078.1 (May 16, 2011); US Appl. No. 61/179,551) — these are record documents, not prior art; they evidence what was already considered.
10. Materials/property references (A&C Plastics 2018; EMCO 2018; Highline Polycarbonate 2018; Swanson et al., "The Strength of the Hand"; "Elongated" dictionary definition) — post-date the 2011 priority (2018) or are generic; usable only for claim-construction/§ 112 support (e.g., the "resilient/flexible vs. rigid-connection" tension flagged in the earlier summary), not as § 102 art.

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5. Overall § 102 assessment

Strongest single-reference (§ 102) candidates, ranked:

1. Burns/Scuf article (Oct. 20, 2010) — closest to disclosing back paddles on a two-hand controller; § 102(a)(1) against claims 1/10/20 if it shows the transition-edge-midpoint positioning and rigid connection. The family's litigation shows the article was battle-tested but the outcome turned on whether it qualified as a printed publication, not only on its content.
2. US 2010/0298053 A1 (Kotkin/Icontrol) — strongest patent reference for non-thumb back actuators; § 103 primary reference, weak § 102.
3. GB 2 481 633 A (Burgess) — thematically on point (underside buttons) but prior art only if the effective date slides to 2015; also an own-inventor disclosure.

The claim limitations that defeat clean anticipation. Every cited reference fails to disclose, in a single embodiment, the combination the independents require: (i) a back recessed portion recessed toward the front relative to the handles, (ii) two elongate members each positioned at/adjacent the midpoint of a handle-to-recess transition edge (claims 1/10), or a single control whose first and second outer edges sit at those two midpoints (claim 20), and (iii) a rigid connection configured to apply a moment to a free end, restricting rotation. The closest art (Kotkin; Scuf; Coe; Inoue) shows that back controls exist, not where (transition-edge midpoints) or how (rigid/moment-applying mount). This is consistent with the '305's claim-drafting strategy of using structural/positional limitations rather than the "resilient and flexible" language of the earlier family members — which is itself the § 112 written-description issue flagged in the earlier summary.

Net conclusion: For US 10,286,305 B2, the cited art is predominantly § 103 (obviousness) material and background; genuine § 102 anticipation is arguable only for the Burns/Scuf article and, secondarily, Kotkin — and even then only on a full element-by-element chart. No cited reference is a clean, uncontested anticipatory reference for independent claims 1, 10, or 20.

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6. Stated uncertainties / conflicts

• Date conflict (persists from earlier section): Google Patents = priority 2011-06-17, filing 2015-06-30; Unified Patents = 2011-06-16, application date 2015-06-29. I treat the Google Patents front-page values as controlling.
• I could not, within this pass, independently pull and read the full disclosure of every one of the 82 references. Tier-2 descriptions are condensed from the citation data and the family's IPR litigation record; the § 102 characterizations for Tier 2 are my assessments, not source statements.
• Effective-date sensitivity is the largest single variable. If the "transition-edge/rigid-connection" limitations are not entitled to 2011 priority, several currently non-prior-art items (Razer Sabertooth 2013; USD711,881; US 2015/0238855) become available, and GB 2 481 633 A becomes squarely available — materially changing the § 102 picture. I have no authoritative record of a priority (derivation/§ 112) challenge to the '305 specifically.
• "Family has litigation" flag on the '305 is family-level; as noted in the earlier section, I found no appellate or IPR docket captioned to the '305 itself. That does not preclude an unindexed or sealed proceeding.

I'll ground this analysis in the prior-art references listed on the patent's own page, plus the PTAB record. Let me pull a few specifics.

Let me verify a few specific references and check whether the '305 itself has any PTAB record.

Obviousness Analysis — US 10,286,305 B2 under 35 U.S.C. § 103

Scope note: This section builds on the bibliographic, claim-construction, and litigation sections already generated for this patent. It does not repeat the claim summaries, Ironburg I/II history, or the IPR2016-00949 record already summarized — it deploys them. Prior art is drawn from the references listed in the Prior Art / Citations / Non-Patent Citations sections of the '305 Google Patents page (https://patents.google.com/patent/[US10286305B2](/patent/US10286305B2)/en), which I treat as the authoritative, examiner-considered art set. Where I could not pin a reference, I say so.

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1. Legal frame and the threshold date problem

The '305 issued from App. 14/754,789, filed 2015-06-30, claiming benefit back to 2011-06-17. That creates an unresolved threshold question that changes the § 103 analysis materially:

• If the '305's claims (as drafted in 2015) are fully supported by the 2011 parent, pre-AIA § 102/§ 103 governs, and prior art must qualify under § 102(a)/(b)/(e)/(f)/(g).
• If the 2015-added claim language ("transition edge," "rigidly connected … configured to apply a moment … thereby restrict rotation") is not supported in the 2011 disclosure, then the AIA applies and § 102(a)(1)/(a)(2) art is available for the newly-added subject matter.

I flag this rather than resolve it; the previously generated section already identified the written-description tension. Practically, it matters most for GB 2,481,633 A (Burgess) — see § 3 below — and for the availability of post-2011 art.

The three Graham factors as I apply them:

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2. Person of ordinary skill in the art (POSITA)

From the record, the parties' POSITA formulations have been contested (the '525 Second Petition response complains of "a senseless qualification to be considered as a POSITA," https://ptacts.uspto.gov/ptacts/public-informations/petitions/[1473194](/patent/1473194)/download-documents). A defensible formulation, and the one I apply:

A person with a bachelor's degree in mechanical engineering, industrial design, or a related field, plus 2–4 years of experience designing handheld consumer-electronics enclosures/input devices (or equivalent industry experience), and familiarity with ergonomic hand-anatomy constraints.

This POSITA knows: cantilever mechanics and beam bending; how a rigidly fixed lever reacts to a tip load (bending moment at the fixed end); standard fastening (screws, adhesive, ultrasonic welding); and the Xbox 360 / PS3 controller chassis conventions — including that the underside of such a controller has two grips and a recessed medial region between them.

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3. The prior-art set (from the '305's own citation list)

Two honesty flags:

1. "Willner" is unresolved. The Federal Circuit opinions (June 18, 2026) and the district court record identify "Willner" only by name; the petition excerpt describing it ("left and right housings 102 and 104," "adaptor 210") matches the Alphagrip-family "hand grippable combined keyboard and game controller system" art appearing on the '305's face (US 6,512,511 / US 6,760,013). I cannot confirm the numeric match from the retrieved sources and treat it as an open item.
2. GB 2,481,633 A (Burgess, "Games console controller with buttons on underside," priority 2010-07-01, published 2012-01-04) appears in the '305 family citations but is probably not available as § 103 art: its publication post-dates the 2011-06-17 priority date, it is not a US patent/publication for § 102(e) purposes, and it is the same inventor's own work (pre-AIA § 103(c) / AIA § 102(b)(2)(A)). It is useful as context for what the field was doing, not as a ground.

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4. The two limitations that carry the whole case

Everything else in claims 1, 10, and 20 is old chassis geometry. The obviousness fight reduces to two limitations.

4.1 "at or adjacent a midpoint of a [handle/]transition edge"

This is a positional/design-choice limitation. Independent claims 1 and 10 place each elongate member at/adjacent the midpoint of the first/second transition edge; claim 20 does the same with points on the control's outer edges.

• A POSITA placing a finger-actuated back control on a conventional dual-grip controller is constrained to the natural resting location of the middle/ring finger — which, on a standard chassis, is precisely the junction where the protruding grip meets the recessed medial back region. The claims' own specification concedes the driver is ergonomic ("the most ergonomically efficient activation … by the middle fingers").
• Legal hook: KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007) ("a court must ask whether the improvement is more than the predictable use of prior art elements according to their established functions"); MPEP § 2144.04 (obvious design choice / aesthetic placement); MPEP § 2144.05 (obvious to vary a parameter). Placement of a known control where the actuating finger naturally falls is the paradigm of an obvious design choice.
• Claim 19 (transition edges converging toward the top) and claims 17/18 (top ends closer together / parallel) are explicitly disclosed as alternative embodiments in the '305's own specification ("In one embodiment the paddles are orientated parallel with each other. In an alternative embodiment the paddles … converge towards the top edge"). Alternative embodiments recited as claims are presumed obvious variants of each other absent evidence of unexpected results — a damaging posture for the patent owner.

4.2 "rigidly connected … configured to apply a moment … thereby restrict rotation"

This is a functional recitation of an inherent mechanical property of a cantilever.

• Any elongate member fixed at one end to a rigid body and loaded at its free end necessarily experiences a reaction moment at the fixed end; that is elementary beam mechanics, not an inventive contribution. The moment is applied and rotation is restricted because the joint is rigid — the claim says nothing more.
• Legal hook: inherency (In re Schreiber, 128 F.3d 1473 (Fed. Cir. 1997); In re Best, 562 F.2d 1252 (CCPA 1977)); and KSR's instruction that a predictable variation of a known structure is obvious. Likewise, the limitation is met by any back-mounted cantilevered lever — Tosaki's shift levers, Enright's mode switches, Kotkin's skin-mounted actuators — since each is anchored and loaded at a free end.
• Claim 3 (rigid connection "by a screw") is disposed of by KSR ("a screw is a screw") — a screw is a known fastening for a known purpose with a predictable result.

Consequence: the '305's independents are, in substance, broader than the '525 family claims the PTAB already cancelled. The '525's claim 1 required the elongate member to extend "substantially the full distance between the top edge and the bottom edge" — a limitation central to the 2026 estoppel dispute, and one that the '305's independents do not contain (the ≥ one-half dimensional limitation sits only in dependents 5 and 11). The '305's drafter appears to have swapped the hard-to-prove "substantially full distance"/"paddle lever" vocabulary for a geometric "midpoint" recitation and an inherent cantilever property. That framing is my analysis of the claim text, not a source statement.

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5. Specific § 103 combinations and motivations

Ground 1 — Tosaki + Enright (+ Ono) — the strongest ground

This is the ground the Board actually instituted and on which it found claims 1–12 and 15–20 of the '770 unpatentable — the '770 being the immediate parent of the '305 (IPR2016-00949 FWD, as amended by the Nov. 15, 2017 errata, https://www.docketalarm.com/cases/PTAB/IPR2016-00949/).

Motivation (articulated): Both references are in the same field (hand-held video game controllers), address the same problem (actuating additional functions without releasing the thumb sticks), and Tosaki is cited for the express purpose of lengthening Enright's existing back controls to improve "easy operation of the device" and ergonomics — a "predictable variation in a predictable art" per the Board's institution decision. KSR endorses exactly this: combining two references that disclose the same device to achieve a predictable improvement.

Claim 13 (Ono): the Board also described a ground of Enright + Tosaki + Ono for the '770's claim 13 (a switch/structure detail), showing that secondary references fill residual mechanical details.

Ground 2 — Kotkin (Icontrol '053 / WO '287) alone or + Tosaki

Kotkin discloses a controller enhancement whose express object is to permit control "with parts of the hand other than the thumbs, such as the side or tip of the index finger," and to "reduce the strain on the hands." Combined with Tosaki's elongate back levers, or standing alone for the back-control concept, Kotkin supplies:

• the back-mounting teaching (claim 1's "located at the back");
• the rigid connection (Kotkin's actuators are mounted to a rigid skin/shell — a fixed anchor, hence a cantilever reaction moment);
• the ergonomic motivation that KSR rewards.

Note: "Kotkin" was actually run at the PTAB by Collective Minds in 2018 as an anticipation ground against the '525, and the 2026 Federal Circuit decision (reversing § 315(e)(2) estoppel) leaves Kotkin and Willner–Koji–Raymond live for trial (https://www.oliff.com/wp-content/uploads/2026/07/2024-2088-O-1.pdf; https://www.schwabe.com/publication/latest-federal-court-cases-ironburg-inventions-ltd-v-valve-corp/). Kotkin's probative value for the '305 is therefore not merely theoretical — it survived the estoppel challenge procedurally.

Ground 3 — Willner + Koji + Raymond (+ Kotkin)

The CMG ground the Federal Circuit has now cleared for trial. Its components all appear on the '305's own citation list or NPL list (Raymond US 5,773,769; Koji JPH1020951), which strengthens the case: the examiner had these references before him, so the patent owner cannot argue non-analogous art or unreasonable discoverability. Raymond's thin lever (0.5 mm steel) combines with the others to supply a thin elongate lever; Koji supplies a multi-stage trigger/actuation mechanism.

Ground 4 — Enright + Tosaki + Nintendo '426 / Thrustmaster '317

If the patent owner successfully argues the "transition edge midpoint" limitation is not disclosed, these chassis references fill the gap: Nintendo '426 discloses the classic two-grip chassis, and Thrustmaster '317 discloses a two-handed controller with back-of-hand controls. Placing Kotkin's actuator or Enright's mode switch at the grip/recess junction on a Nintendo-'426-style chassis is a design choice with predictable ergonomic results.

§102 note

For completeness: Kotkin alone was asserted as an anticipation ground (not just obviousness) against the '525. Whether Kotkin or Tosaki alone anticipates any of the '305's 21 claims depends on the "midpoint" and "moment" limitations being read as inherent; if read narrowly, they don't anticipate and the analysis stays under § 103.

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6. Dependent claims

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7. What the patent owner will argue, and how it fares

1. Hindsight / "piecemeal reconstruction." Already litigated: the Board rejected the same hindsight argument in IPR2016-00949 and instituted anyway. KSR forecloses the "teaching away or nothing" framing.
2. "Paddle lever" ≠ any switch. Rejected as to claims 1/10/20, which don't use the term; live only as to dependent claim 4.
3. Non-analogous art. Weak — every reference is in hand-held video game controllers. Kotkin, Tosaki, Enright, Ono all share the field of endeavour and the problem addressed.
4. The "midpoint of a transition edge" is not disclosed. The strongest defense. It is a pure design-choice argument that the patent owner will need to rebut with objective evidence of unexpected results — which the specification does not report.
5. § 112 indefiniteness. The '305 contains a measurement-type limitation ("at or adjacent a midpoint") of the species the Federal Circuit has found problematic in this family (see the earlier summary's § 112 flag and the prior Fed. Cir. discussion of measurement-claim indefiniteness in this litigation). If the claim is indefinite, the § 103 question is moot. Worth pursuing in parallel.

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8. Objective indicia (secondary considerations) — mixed

For the patent owner:

• Licensing: Microsoft entered a license in October 2015 covering the '525, and Scuf Gaming is a licensee (https://ptacts.uspto.gov/ptacts/public-informations/petitions/1473194/download-documents).
• Long-felt need / failure of others: Microsoft "did not sell any video game controllers that had back controls on the back of the controller" prior to the license, and the Xbox Elite Wireless Controller (2015) post-dates the 2011 priority date. This is the strongest secondary consideration the patent owner has advanced.

Against:

• The nexus is weak for the features now at issue: the district court noted that the accused feature — "the two back controls comprised of elongate members" — was declared invalid by the PTAB and "not themselves protected by the '525 Patent." Licensing of a patent whose broad claims were cancelled funds little weight for the narrow claims.
• The district court rejected Ironburg's copying argument, finding Valve's engineers "were not even aware of the '525 patent while designing the commercial version of the Steam Controller" (https://storage.courtlistener.com/recap/gov.uscourts.wawd.[248491](/patent/248491)/gov.uscourts.wawd.248491.475.0.pdf).
• The 2010 Burns article — held to be a publicly accessible printed publication (Valve v. Ironburg, Fed. Cir.) — shows a commercial back-paddle controller in the market before the priority date, cutting against long-felt need.

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9. Bottom line

My assessment: claims 1, 10, and 20 of the '305 are more likely than not invalid under § 103, with the probability highest for the combination of Tosaki + Enright (+ Ono) and Kotkin, and materially weaker for any claim drawn solely to the precise "midpoint" placement without a supporting chassis reference.

Confidence levels:

• High — claims 1–3, 5–6, 10–13, 17–19, 20–21 are obvious over Tosaki + Enright + a conventional-chassis reference (Nintendo '426 / Thrustmaster '317), because the only non-chassis limitations are a design-choice placement and an inherent cantilever property.
• Moderate — claim 4, because the "paddle lever" construction has been contested and the Board has previously refused to read it onto any control member.
• Moderate/uncertain — the outer boundary of claims 7–9 and 14–16 (specific geometric keying) absent an explicit chassis reference disclosure of "convex portions + medial portion."

Open items I could not resolve:

1. Whether the '305's 2015 claim language enjoys 2011 written-description support (determines pre-AIA vs. AIA art).
2. The exact identity of the "Willner" reference.
3. Whether any IPR or CAFC docket names the '305 itself — consistent with the earlier section, I found none; all 2026 appellate activity I located concerns the '525, '770, '229, and '688 patents.

Date note (carried forward): the prompt states April 26, 2026, while retrieved materials include a June 18, 2026 precedential Federal Circuit opinion and post-remand docket activity. Per instruction to prefer retrieved results, I have treated those 2026 items as current.