US 8215816

I'll search for authoritative information on US patent 8215816, including any recent CAFC docket activity.

Let me check for any Federal Circuit (CAFC) activity and current litigation status.

Let me verify the IPR outcome and check for any Federal Circuit appeal.

US Patent 8,215,816 B2 — "Light emitting panel assemblies"

Bibliographic data (as recorded)

Abstract (verbatim)

"A light emitting assembly comprises a light source, a light emitting panel member having an input edge that receives light from the light source, and end edge and side edge reflectors. The panel member is received in a cavity or recess of a tray or housing. An additional component overlies the panel member. Light extracting deformities on or in a surface of the panel member cause light to be emitted from the panel member."

Plain-language overview of the claims

Claim 1 (the only independent claim) — a light-emitting assembly made up of:

1. At least one light source.
2. A light emitting panel member (a light guide) with (a) at least one input edge that receives light from the source, and (b) a light emitting surface. The panel is wider than it is tall (a flat, wide panel).
3. A tray or housing with a cavity/recess in which the panel member is entirely received (the tray wraps the whole panel).
4. A pattern of light extracting deformities on or in at least one surface of the panel that causes light to exit the light emitting surface.
5. End edge reflectors and side edge reflectors (reflectors along the ends and the long sides).
6. An additional component overlying the panel member (e.g., a film, diffuser, display, or overlay).
7. The light input edge has a refractive surface that redirects the light output distribution of the source more in the width direction as the light enters the panel (i.e., the input edge spreads the beam laterally so it fans out across the panel's width).

Claim 2 — narrows claim 1 in that the end and side edge reflectors are located on the end edges and side edges of the panel member itself.

Claim 3 — alternative placement: the end and side edge reflectors are located on the end walls and side walls of the tray or housing (rather than on the panel).

Claim 4 — the at least one light source comprises one or more LEDs.

Prosecution history / family

The '816 patent is a continuation deep in a long family. Per the specification's cross-reference: it is a continuation of Ser. No. 12/940,424 (now US 8,142,063), itself a continuation chain back through 12/488,617, 12/246,613, 11/504,203 (US 7,467,887), 10/784,527 (US 7,160,015), and 09/256,275 (US 6,712,481), which is a CIP of 08/778,089 (US 6,079,838), a division of 08/495,176 (US 5,613,751, filed June 27, 1995). The Google Patents family (ID 23967579) lists 15 U.S. family applications, plus EP 0751340 B1, DE 69608499 T2, and five JP members.

Post-grant and litigation history

• The patent was heavily asserted in 2013–2014 district court litigation in the District of Delaware and the Eastern District of Texas (numerous case numbers are listed on the Google Patents page).
• PTAB: several IPRs were filed. The one that reached a merits decision was IPR2015‑01866, K.J. Pretech Co., Ltd. v. Innovative Display Technologies LLC, filed Sept. 11, 2015, challenging claims 1, 3, and 4. It was instituted March 17, 2016, and reached a Final Written Decision on March 15, 2017, with third‑party databases recording the outcome as "Unpatentable" (i.e., the challenged claims were held unpatentable). Other IPRs on this patent were terminated by settlement or not instituted: IPR2015‑00366 (settlement), IPR2015‑00752 (settlement), IPR2015‑00834 (settlement), IPR2015‑01114 (settlement), IPR2015‑00496 (not instituted – procedural), and IPR2014‑01095 (not instituted – merits).

CAFC 2026 dockets — search result

I found no Federal Circuit (CAFC) 2026 docket activity for US 8,215,816. My searches of Federal Circuit/appellate dockets returned no hits for this patent number, and no appeal from IPR2015‑01866 was surfaced. Given that (a) the patent's term expired June 27, 2015, (b) the PTAB's 2017 final written decision invalidated the challenged claims, and (c) the patent carries "Expired – Fee Related" status, there is no apparent basis for live 2026 appellate activity on this patent. I cannot state with certainty that no notice of appeal was ever filed from IPR2015‑01866; I simply found no record of one.

Explicit uncertainties

• Assignee: the operative owner as of the last recorded assignment is Innovative Display Technologies LLC; FreePatentsOnline's "Rambus International Ltd." listing is the assignee at the time of issue. I am reporting both rather than choosing one.
• IPR outcome detail: I could not read the text of the March 15, 2017 Final Written Decision itself in these searches; the "Unpatentable" characterization comes from a third‑party PTAB analytics source. Treat the specific claim‑by‑claim result as provisional.
• Do not confuse this patent with unrelated patents that are also informally called "the '816 patent" (e.g., US 10,270,816, litigated by Hammond Development International, which appears in some search results). Those are different documents and are not covered here.

If you need the exact language of the Final Written Decision in IPR2015‑01866 or confirmation of any notice of appeal, those would require pulling the PTAB record (PAPER filings) and the Federal Circuit's CM/ECF docket directly.

I'll research litigation involving US patent 8215816 using the sources you specified.

Let me gather details on the specific cases and parties.

Litigation Involving U.S. Patent No. 8,215,816

Patent: U.S. 8,215,816 B2 ("Light Emitting Panel Assemblies"), inventor Jeffery R. Parker, application 13/315,412, priority date June 27, 1995, granted July 10, 2012. Current assignee: Innovative Display Technologies LLC (originally Rambus International Ltd; reassigned through Rambus Delaware → Acacia Research Group → Innovative Display Technologies). Legal status: Expired – Fee Related (anticipated expiration June 27, 2015).

Bottom line: Yes — this patent was heavily litigated. It was asserted as part of a large multi-patent campaign by Innovative Display Technologies LLC ("IDT") and affiliate Delaware Display Group LLC ("DDG") against dozens of technology and automotive defendants in the Eastern District of Texas and District of Delaware, and it was the subject of at least seven PTAB inter partes reviews. Note the patent's term expired June 27, 2015, so post-2015 activity concerns pre-expiration damages only.

Note on scope: my consolidated source (the patent page's own litigation docket) lists case numbers but generally not party names; the party names below come from separate docket databases. Where I could not verify a party name, I say so rather than guess.

A. District Court Litigation (Eastern District of Texas)

Almost all E.D. Tex. cases were consolidated for pretrial purposes into lead case 2:14-cv-00201 (Judge Rodney Gilstrap, Marshall Division). Patents asserted across these suits: 6,755,547; 7,300,194; 7,384,177; 7,404,660; 7,434,974; 7,537,370; 8,215,816.

Other E.D. Tex. matters reported:

• IDT v. Acer Inc. (and [Microsoft Corp.](/litigations/by-plaintiff/Microsoft%20Corp.), et al.) — claim construction in 2014 before Judge Payne; the court issued a Claim Construction Memorandum and Order (Aug 26, 2014) and invalidated one claim as indefinite under 35 U.S.C. § 112(2) ("quite small" term). The '816 patent was among the patents-in-suit.
• IDT v. Volkswagen AG et al. — filed Apr 7, 2014; Volkswagen/Audi moved to dismiss (June 2014) on grounds the allegations covered "essentially every" VW/Audi vehicle sold in the U.S.
• IDT + DDG v. T-Mobile US, Inc. and T-Mobile USA, Inc. — complaint asserting the '816 patent among others.
• IDT v. LG Display Co., Ltd. et al. — Case No. 2:16-cv-00932, filed Aug 24, 2016 (E.D. Tex., Judge Gilstrap); defendants included LG Display, LG Electronics entities, Vizio, ASUSTeK, and ASUS Computer International.
• IDT v. Dell Inc., Hewlett-Packard Co., BlackBerry, Acer, Huawei, ZTE — reported multi-defendant suit naming the '816 patent (7 patents total).

B. District Court Litigation (District of Delaware)

Filed by Delaware Display Group LLC and/or IDT (Judge Richard G. Andrews). These cases largely concerned the related '196 patent along with the IDT patents:

C. PTAB Proceedings (Inter Partes Review)

Conflict flagged (IPR2015-01114): Your source material classifies IPR2015-01114 as "Settlement," while a separate PTAB-tracking database reports the status as "Institution Denied" with an institution decision date of July 2, 2015. I am reporting both rather than resolving them; the two are not necessarily inconsistent (institution could have been denied procedurally and the matter dismissed/settled). Verify against PTAB's own records (Patent Trial and Appeal Board End of Proceeding / Patent Trial and Appeal Board docket) for the authoritative disposition.

D. Key Caveats

• "Not verified" party names reflect cases listed on the patent's own litigation docket where I could not independently confirm defendant identities from the sources searched. Confirm via PACER before relying on them.
• Judge: Most E.D. Tex. cases were before Judge Rodney Gilstrap; the Delaware cases were before Judge Richard G. Andrews.
• Outcomes: Most cases resolved by dismissal, settlement, or consolidation rather than trial. The only merits rulings I surfaced are the 2014 Acer claim-construction/indefiniteness ruling (a claim invalidated as indefinite) and the IPR2015-01866 Final Written Decision. I do not have verified final judgments in the remaining individual cases.
• Provenance of the case list: The consolidated list of case numbers (Section A and B) comes from the patent record's "Family has litigation" section, which draws on Unified Patents litigation data and Darts-IP, with links on the patent page. Individual party names come from Justia Dockets, PlainSite, UniCourt, Stanford NPE Litigation Database, Law360, and GreyB/IPVerse.

Recommended verification sources: PACER (case-specific dockets), the USPTO PTAB docket for the IPR numbers above, and Unified Patents' litigation portal (https://portal.unifiedpatents.com/litigation/caselist), which is the source behind many of the case numbers listed on the patent record.

Two items I could not confirm with high confidence and would flag as needing direct verification: (1) the ultimate disposition of each individual 2014 E.D. Tex. case, and (2) whether any Federal Circuit appeal (CAFC) was taken from the IPR2015-01866 Final Written Decision. I did not find a CAFC appeal in the sources searched, but I cannot affirmatively state that none exists.

I'll research the PTAB proceedings before writing. Let me start with targeted searches.

Let me dig into each proceeding and identify which one targets US8215816.

Good progress. Now let me pin down the outcomes and the remaining proceeding numbers.

I'll research the assignment record for US 8,215,816 across USPTO Assignment Center, SEC filings, and NPE asserter directories.

Assignment & Ownership Reconstruction — US 8,215,816 B2

Data provenance note (read first): The USPTO Assignment Center (assignmentcenter.uspto.gov / assignment.uspto.gov) and its third-party mirrors were not machine-readable in the searches available to me. I could retrieve the parties, dates, and conveyance direction for this patent's post-issuance chain from Google Patents' legal-events record (which is ingested from USPTO assignment data) and from court opinions that recite the underlying assignment agreements. I could NOT retrieve the reel/frame numbers or the correspondent-of-record fields for the '816 patent's own recordings. I have therefore left those fields marked [not retrieved] rather than guessing. Where I surface a reel/frame, I say explicitly why it may or may not attach to this patent. Fabricated reel/frame numbers would be worse than blanks here.

Inventors

Unusual-pattern check — inventor retention: No "inventor bailout" pattern. The opposite is present: the same inventor (Parker) and a stable engineering group (Timothy A. McCollum, Robert M. Ezell, Kurt R. Starkey, Fumitomo Hide, Martin E. Ligas, Gregg M. Podojil — all appearing on Rambus Delaware LLC filings) stayed with the technology business unit as it passed Lumitex → Solid State Opto → Rambus → Rambus Delaware LLC. The asset that migrated away is the patent portfolio, not the people — which is the classic signature of a monetization carve-out rather than an operating-company failure.

Employer-of-record caveat: the 2011 continuation that issued as the '816 was filed by Rambus International Ltd., not by Lumitex or SOL. So for assignment purposes Rambus International Ltd. is the applicant/owner at issue; for provenance purposes the invention is Lumitex/SOL lineage.

Original assignee

Rambus International Ltd. (Ky./offshore IP-holding subsidiary of Rambus Inc., NASDAQ: RMBS) is the assignee named on the face of the issued patent, per Google Patents' "Original Assignee" field and the Dec. 9, 2011 filing entry.

• Did they ship a product embodying the claims? Not directly on this patent. Rambus is a semiconductor IP and technology licensing company, not an LCD panel or backlight module manufacturer. The commercial embodiment lineage traces to Lumitex, Inc. (Cleveland, Ohio), which made backlighting/light-guide products, then to Solid State Opto Limited, a joint venture formed after Lumitex divested its optical division to Mang-Shiang (Lee) Lee. Rambus acquired the display/lighting portfolio effective December 2009 (court record: "Rambus owned the patents-in-suit for a period of approximately three years, from December 2009 until January 2013") for a reported ~US$26 million, with SOL retaining a license-back right. Rambus itself disclosed LED/display development activity but did not manufacture a panel assembly practicing these claims.
• Primary line of business: memory interface/security IP licensing and, later, chips and silicon IP. Rambus Inc. is operating and publicly traded (RMBS) as of 2026; Rambus International Ltd. and Rambus Delaware LLC are internal holding vehicles.
• Current status of the original assignee of record: operating parent, not dissolved, not in bankruptcy. The patent itself is status "Expired – Fee Related," with anticipated expiration June 27, 2015 (20 years from the June 27, 1995 priority date).

Contradiction flagged vs. the earlier section: the previously generated summary listed "Rambus International Ltd." as current assignee on FreePatentsOnline and "Innovative Display Technologies LLC" as current owner of record. Both are correct as to their respective dates; the Google Patents legal-events entries (below) control the ownership question. I am not aware of any post-2013 recording moving title back to a Rambus entity.

Assignment timeline

Chronological, for US 8,215,816 B2. Reel/frame and correspondent fields are [not retrieved] — see provenance note.

1. ~2009-12-xx (executed) / recorded [not retrieved] — Reel [not retrieved]

• Conveyance: Assignment
• Assignor: Solid State Opto Limited (and/or Mang-Shiang Lee)
• Assignee: Rambus International Ltd.
• Correspondent: [not retrieved]
• Context: Portfolio acquisition — Rambus buys the Lumitex/SOL backlighting portfolio (~$26M reported), taking title in its offshore IP-holding subsidiary. Recorded against the family; exact date for the '816 itself not isolated because the '816 did not yet exist (filed 2011).

**2. [executed date not retrieved] / recorded 2013-03-04 — Reel [not retrieved]

• Conveyance: Assignment (internal reorganization)
• Assignor: Rambus Inc.
• Assignee: Rambus Delaware LLC
• Correspondent: [not retrieved]
• Context: Internal reorg — title consolidated into the Rambus Delaware IP-holding vehicle ahead of the Acacia sale. Note the intermediate Rambus International Ltd. → Rambus Inc. step is documented in the STPI/USPTO-derived chain but is not separately shown among the '816 legal events on Google Patents; flagging that gap rather than asserting a date.

**3. 2013-01-30 (executed) / recorded 2013-06-26 — Reel [not retrieved]

• Conveyance: Assignment (sale with retained profit participation)
• Assignor: Rambus Delaware LLC
• Assignee: Acacia Research Group LLC (Acacia Research Corporation, NASDAQ: ACTG)
• Correspondent: [not retrieved]
• Context: Transfer-to-asserter — court record: "On January 30, 2013, Rambus sold the patents-in-suit to Acacia… Rambus would not retain any legal interests in the patents-in-suit, but would receive a certain percentage of any proceeds collected through licensing or litigation." Publicly announced March 7, 2013 via BusinessWire ("Rambus Transfers Display Patents to Acacia Research Subsidiary"), with Rambus retaining a license to use the patents. Note the ~5-month gap between the January execution and the June recording date shown on Google Patents.

**4. 2013-06-27 (per Google Patents recording) / recorded 2013-06-27 — Reel [not retrieved]

• Conveyance: Assignment
• Assignor: Acacia Research Group LLC
• Assignee: Innovative Display Technologies LLC ("IDT")
• Correspondent: [not retrieved]
• Context: Transfer-to-asserter / pre-litigation setup — IDT was formed March 13, 2013, days after the Acacia recording. See discrepancy note below.

Discrepancy flagged (do not paper over): the Delaware Display Group LLC v. Lenovo Group Ltd. opinion (2016 WL 720977, D. Del.) states "On July 26, 2013, Acacia assigned 'all of the right, title and interest in the' patents-in-suit to [IDT]", whereas Google Patents' legal events for the '816 record the Acacia → IDT assignment as 2013-06-27. These may refer to different patents in the seven-patent group, to execution vs. recording dates, or one source may be imprecise. Both are reported here; the operative point — that the assignment landed on the eve of suit — is unaffected.

5. 2020-04-xx (executed) / recorded at REEL/FRAME 052853/0153 — corroborated reel/frame

• Conveyance: Patent Security Agreement (collateral pledge, not a title transfer)
• Assignor: Acacia Research Group LLC, American Vehicular Sciences LLC, Bonutti Skeletal Innovations LLC, and others — including "INNOVATIVE DISPLAY TECHNOLOGIES LLC, TEXAS"
• Assignee/Secured party: Starboard Value Intermediate Fund LP, as Collateral Agent (New York)
• Correspondent: [not retrieved]
• Context: Securitization — a blanket security interest recorded over the Acacia-family entity portfolio. I encountered IDT's name in the collateral roster in search results; I could not verify that the '816 patent is individually listed on the collateral schedule, so treat this as a portfolio-level encumbrance lead, not a per-patent finding. A Release of Security Interest was recorded at REEL/FRAME 053654/0254 with a 2020-06-30 effective date.

No further assignment records retrieved. The 2013 IDT link is the terminal ownership entry I can evidence. There is no recorded transfer to a defensive aggregator (RPX / AST / LOT / Unified / OIN) for this patent.

Timeline diagram

timeline
    title Ownership of US 8215816
    1995 : Original Lumitex application filed
    1997 : Continuation chain continues
    2009 : Display portfolio acquired by Rambus
    2012 : Continuation issues as US 8215816
    2013 : Rambus to Rambus Delaware recorded
         : Rambus sells portfolio to Acacia
         : Acacia assigns patent to IDT
         : IDT files first suits the next day
    2015 : Patent term expires
    2017 : PTAB invalidates challenged claims

NPE / troll-pattern signals

1. Shell-entity transfer — PRESENT.
The patent moves from an IP-holding operating-affiliate (Rambus Delaware LLC) to a licensing-only LLC (Acacia Research Group LLC, then Innovative Display Technologies LLC). Concrete evidence, not naming inference: IDT was formed March 13, 2013 — 14 days before the recorded June chain completed; it is registered at 1701 Directors Blvd, Suite 300, Austin, TX 78744, an address shared with a roster of other Acacia subsidiaries (Database Sync Solutions LLC, Brilliant Optical Solutions LLC, Cellular Communications Equipment LLC, RFID-Rx LLC, Progressive Semiconductor Solutions LLC, and others); press reporting states IDT "doesn't make any products or even have its own website" and that its only employees are outside law firms. Acacia's own collateral filing lists "INNOVATIVE DISPLAY TECHNOLOGIES LLC, TEXAS" (REEL/FRAME 052853/0153), confirming the entity is real but asset-shell in character.

2. Known asserter in the chain — PRESENT.
Both Acacia Research Group LLC and Innovative Display Technologies LLC are public NPE-list entities. United Patents' PTAB portal classifies the owner of IPR2014-01096 (same family, '370 patent) as "NPE (Patent Assertion Entity)" with real parties-in-interest "Acacia Research Corp / Acacia Research Group LLC / Innovative Display Technologies LLC." RPX describes IDT/DDG as "the Acacia subsidiary" and "the NPEs." Third-party counts put IDT at 34–37 filed suits; the broader Acacia roster at ~63 subsidiaries and ~669 suits. IDT is also the patent owner of record in the eight-patent group asserted in this campaign (6,755,547; 7,300,194; 7,384,177; 7,404,660; 7,434,974; 7,537,370; 7,914,196; 8,215,816).

3. Repeat correspondent across the chain — UNCLEAR / NOT VERIFIED.
I could not retrieve the correspondent of record on any of the three 2013 recordings for this patent, so I cannot make a recurrence finding. Two leads, explicitly labeled as unverified:

• Schulte Roth & Zabel LLP (S. Karff), 919 Third Avenue, New York, NY 10022, together with Robert Allan Bullwinkel, 1111 Bagby St, Suite 2100, Houston, TX 77002, appeared as correspondents on an Acacia Research Group LLC recording I encountered in a PTAB exhibit (that exhibit referenced a Reel/Frame 044625/0315 for an Acacia Research Group LLC assignment). I could not confirm that this reel/frame or these correspondents attach to the '816 patent — do not treat as established.
• Separately, and clearly not an assignment correspondent: Bragalone Conroy PC (Justin B. Kimble, Jeffrey R. Bragalone) is IDT's PTAB litigation counsel of record (e.g., IPR2015-01113, '660 patent), and Eric Lucas acted as in-house counsel for Acacia and later IDT/DDG (D. Del., DDG v. Lenovo). These are repeat-player signals for the campaign, not for the assignment records.

4. Cascading transfers — PRESENT.
Three recorded transfers in roughly 115 days (Rambus Delaware LLC ← Rambus Inc. on 2013-03-04; → Acacia Research Group LLC recorded 2013-06-26; → IDT 2013-06-27), stacked on the upstream SOL → Rambus International → Rambus Inc. → Rambus Delaware chain. The Acacia entities share a common parent, a common real party-in-interest (Acacia Research Corporation), and share the Austin address with a dozen sibling LLCs.

5. Pre-litigation transfer — PRESENT (strongest signal).
The assignment to IDT is recorded 2013-06-27; the first infringement suits naming this patent were filed 2013-06-28 — one day later (IDT v. Acer, 2:13-cv-00522; IDT v. Dell, 2:13-cv-00523; IDT v. HP, 2:13-cv-00524; IDT v. Huawei, 2:13-cv-00525; IDT v. Blackberry, 2:13-cv-00526; IDT v. ZTE, 2:13-cv-00527 — all E.D. Tex., Marshall Division). This is a textbook standing/venue-priming transfer.

6. Bankruptcy fire-sale — NOT PRESENT.
No bankruptcy of Rambus, Lumitex, or SOL is implicated. The Rambus → Acacia deal was a negotiated monetization transaction with retained profit participation, not a distressed sale.

7. Privateering — PRESENT (qualified).
Rambus, an operating/licensing company with ongoing display and lighting development, transferred the portfolio to an NPE while retaining a license-back and "a certain percentage of any proceeds collected through licensing or litigation" (D. Del., DDG v. Lenovo), and then entered a March 25, 2013 consulting agreement to perform product "teardowns" directed by Acacia's counsel "in anticipation of potential litigation." That is the privateering structure — originator keeps economic upside and supplies technical ammunition while the NPE fronts the assertion. The qualifier: Rambus was not transferring to attack direct competitors in its core memory business.

8. Defensive aggregator (anti-NPE) — NOT PRESENT as a terminal owner.
The chain does not terminate at RPX, AST, LOT, Unified Patents, or OIN. However, the patent's claims were neutralized by defensive IPR rather than by acquisition: Unified Patents filed IPR2015-00752, IPR2015-00834, and IPR2015-01114 (all terminated by settlement), while K.J. Pretech Co., Ltd. v. Innovative Display Technologies LLC, IPR2015-01866 (filed 2015-09-11 against claims 1, 3, and 4; instituted 2016-03-17) reached a Final Written Decision on 2017-03-15 recorded by third-party analytics as Unpatentable. That is a defensive-IP outcome, not a defensive-aggregator ownership outcome. (Per the earlier section: the claim-by-claim text of that FWD was not verified.)

Additional context signal — Acacia's license/notice dispute: In Innovative Display Technologies LLC v. [Microsoft Corp.](/litigations/by-plaintiff/Microsoft%20Corp.), 2:13-cv-00783 (E.D. Tex.), the court found Acacia Research Corporation a necessary party because of a 2010 Microsoft–Acacia license and an "Updating of ARC Patents" notice clause; the seven Acacia subsidiaries filed on October 1, 2013, the day after Microsoft's license lapsed. This illustrates deliberate timing discipline across the Acacia sub-entities, consistent with the one-day pre-suit transfer seen here.

Verdict

NPE — high confidence.

Four independent strong signals converge: (i) transfer-to-asserter with a same-day-fresh assignee — the Acacia Research Group LLC → Innovative Display Technologies LLC assignment recorded 2013-06-27, with IDT formed only on 2013-03-13 and the first suits filed 2013-06-28, one day later; (ii) shell-entity transfer — IDT is a no-product, no-website Austin LLC sharing 1701 Directors Blvd with a dozen sibling Acacia shells, and appears as "INNOVATIVE DISPLAY TECHNOLOGIES LLC, TEXAS" on Acacia's own collateral filing at REEL/FRAME 052853/0153; (iii) known asserter in the chain — both Acacia Research Group LLC and IDT are publicly listed NPEs and Unified Patents' PTAB portal codes their ownership as "NPE (Patent Assertion Entity)"; and (iv) cascading transfers — three recorded title moves in ~115 days through commonly controlled entities, atop a Rambus→Acacia sale that left Rambus with a license-back and a percentage of litigation proceeds, i.e., a privateering structure. The single caveat to this verdict is evidentiary, not substantive: I could not verify reel/frame numbers or the correspondent of record for the '816 recordings, so signal 3 (repeat correspondent) is unresolved rather than negative.

Verify at: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (search "8215816"; the indexed mirror at https://assignment.uspto.gov/patent/index.html returns the same records). Cross-check the PTAB dockets at https://portal.unifiedpatents.com/ptab/case/IPR2015-01866 and the Acacia real-party-in-interest statements in IPR2015-01113.

I'll research the prior art cited for US 8,215,816 B2 and related references.

Let me pull the full prior-art citation lists from the patent record itself.

Scope, sources, and an important caveat up front

I searched for the exact grant US 8,215,816 B2 (application 13/315,412; filed 2011‑12‑09; granted 2012‑07‑10; assignee of record at grant Rambus International Ltd.; inventor Jeffery R. Parker). I deliberately excluded look‑alike numbers such as US 10,270,816 (Hammond Development) and US 8,305,834/8,142,063, which are different documents (8,305,834 and 8,142,063 are siblings in the same family, not the patent at issue).

Caveat you should read before the tables. The authoritative Google Patents text supplied for US 8,215,816 does not reproduce the "Patent Citations" (backward‑reference) section — it only shows forward citations ("Cited By (4)" and "Families Citing this family (526)"). The sibling page US 8,305,834 shows "Patent Citations (170)" for that family, which tells us the family carries roughly 170 examiner‑cited references. I was able to recover only a partial list (the FreePatentsOnline "US Patent References" list, which is truncated mid‑entry, plus the full exhibit list from IPR2015‑01866). I could not retrieve all 170 citations, and I could not retrieve the PTAB Final Written Decision text itself. Where I am not certain of a date I say so rather than guess.

I flag one contradiction with the earlier section: the earlier section states IPR2015‑01114 was terminated by "Settlement." The PTAB analytics page (ipverse/GreyB) instead reports IPR2015‑01114 as "Institution Denied" (institution decision July 2, 2015; petitioner Mercedes‑Benz USA LLC et al.). Both sources are third‑party; the discrepancy is unresolved in my data and should be checked against the PTAB docket.

1. The controlling finding: the operative §102 reference is Tsunoda (JP 6‑51130)

For this patent, the prior art that actually anticipated claims is not primarily the examiner's face citations — it is the art in IPR2015‑01866, K.J. Pretech Co., Ltd. v. Innovative Display Technologies LLC (filed Sept 11, 2015; instituted Mar 17, 2016; FWD Mar 15, 2017). The petition's Ground 1 was a pure §102 anticipation ground over JP 6‑51130 (Tsunoda) against claims 1, 3, and 4 (claim 2 was not challenged). The Patent Owner's Response of July 1, 2016 argued the one missing limitation was:

"the light input edge has a refractive surface that redirects the light output distribution of the light source more in the width direction as the light enters the panel member"

and argued Tsunoda prevents rather than promotes width‑direction spreading (using reflective notches (2)/(2′) between point sources). The third‑party PTAB analytics record the FWD outcome as "Unpatentable," i.e., Tsunoda was found to anticipate claims 1, 3 and 4. So the single most relevant piece of prior art for US 8,215,816 is:

Note the date logic: the '816 patent claims a June 27, 1995 priority, but the issued claim 1 recites the "input‑edge refractive surface that redirects … more in the width direction" limitation, which is new matter traceable to the Feb. 23, 1999 CIP (Ser. No. 09/256,275). That is why mid‑1990s art such as Tsunoda, and even later art, can be cited against these claims.

2. The IPR2015‑01866 exhibit set (the merits prior art)

From the PTAB exhibit list (ipverse/GreyB, case IPR2015‑01866):

Because claim 1 requires all of: panel with input edge + emitting surface, a tray/housing cavity in which the panel is entirely received, light‑extracting deformities, end and side edge reflectors, an additional component overlying the panel, panel wider than tall, and the width‑redirecting input‑edge refractive surface — most of the above are secondary/§103‑type art that supply only one or two elements. Only Tsunoda was pressed (and, per the FWD, sustained) as a single‑reference anticipation of claims 1, 3, 4.

3. Examiner/face citations recovered (FreePatentsOnline "US Patent References")

These are the U.S. patent references listed on the patent record (partial — the list was truncated). Dates are issue dates, given to month/year; I did not independently verify each, so treat them as provisional.

Honest assessment of §102 for these face citations: on their own, the majority are directed to optical films, prism sheets, or general edge‑lit backlight guides, and none that I can see discloses the entire combination of claim 1 — in particular the tray/housing cavity entirely receiving the panel together with end and side edge reflectors plus the width‑redirecting input‑edge refractive surface. They are, in my read, §103 (obviousness) art or background, not single‑reference anticipatory art — with the exception of the Tsunoda reference above and possibly Mabuchi (US 6,565,225) and Pristash (US 5,005,108) for the input‑edge/panel elements in isolation.

4. Cross‑family / related‑application references (not §102 anticipatory)

The patent's Related U.S. Application Data chain — US 5,613,751 → 5,618,096 → 5,876,107 → 5,921,652 → 6,079,838 → 6,712,481 → 7,160,015 → 7,467,887 → 7,513,672 / 7,524,101 / 7,563,012 / 7,798,695 / 8,142,063 / 8,308,334 — are the same family/same disclosure. They are related applications, not prior art in the ordinary §102 sense (an application is not prior art against its own continuation). I list them here only to prevent them being mistaken for third‑party prior art.

5. Bottom line — claim‑by‑claim §102 map

6. Confidence and remaining gaps

• High confidence: the identity of the patent; the IPR2015‑01866 parties/dates; that Tsunoda (JP 6‑51130) was the primary §102 reference against claims 1, 3, 4; the composition of the IPR exhibit set.
• Moderate confidence: that the FWD held the challenged claims unpatentable (source is a third‑party analytics page, not the FWD text itself).
• Low confidence / not verified: the exact issue dates of the individual cited U.S. patents in §2–§3 (I gave month/year from memory of the FPO list and did not verify each); the filing dates of those references, which I do not have at all; the complete citation list (the Google Patents text for '816 omits it; FPO truncates it; the family reports ~170 references).
• To close the gaps, pull (a) the full "References Cited" section from USPTO PatentCenter / the '816 printed patent front page, and (b) the PAPER filings of IPR2015‑01866 (especially the Feb/Mar 2017 Final Written Decision) to confirm the precise claim‑by‑claim disposition and any appeal.

If you can point me to the front‑page PDF or the PTAB PAPER list, I can expand §3 to the complete ~170‑reference set and map each one precisely.

I'll research the prior art and the specific grounds used against this patent before building the § 103 analysis.

Let me pin down the outcome of the IPR and details on the key references Taylor.

Let me confirm the final outcome and check the "additional component" and "end/side edge reflectors" mappings.

Obviousness Analysis — U.S. Patent No. 8,215,816 B2 under 35 U.S.C. § 103

Building on the previously generated Patent Summary, Litigation Summary, and PTAB Challenges sections. I do not repeat the bibliographic/claim recitations or the docket tables; where I rely on them I cross-reference them.

0. Preliminary flags (contradictions / uncertainties surfaced)

Two things in the previously generated material are directly relevant to the § 103 analysis, and I flag them rather than resolve them silently:

1. Priority date discrepancy. Everywhere else in the record the effective priority date is June 27, 1995 (the filing date of application 08/495,176, US 5,613,751; the Board's institution decision confirms the '816 patent "expired on June 27, 2015," i.e., 20 years from the 1995 date). However, Patent Owner's Preliminary Response in IPR2015-01866 states "The '816 patent claims priority back to June 15, 1995." I treat June 27, 1995 as controlling and the "June 15" recitation as an apparent error in that filing. This matters because it defines the § 103 critical date (see § 2 below).
2. Which IPR grounds were actually instituted. The institution decision states the Board "institute[s] an inter partes review of claims 1, 3, and 4 of the '816 patent based on the ground identified in the Order section" (singular "ground"). The Petitionsummaries in the search results list three grounds (Tsunoda § 102; Pristash § 103; Pristash+Suzawa § 103). It is therefore possible that only the § 102 Tsunoda ground was instituted and the two § 103 grounds were denied at institution. I could not read the "Order" section to confirm. This is a material gap for anyone relying on the IPR as an adjudicated § 103 holding.

1. Framework and the person of ordinary skill

Legal standard. Obviousness is measured under Graham v. John Deere Co., 383 U.S. 1 (1966) (scope/content of prior art; differences; level of ordinary skill; secondary considerations), as refined by KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007) (a combination is obvious where elements were known and combined "according to known methods to yield predictable results"; a "mere substitution of one known element for another"; "use of known technique to improve similar devices in the same way").

Claim construction. Because the '816 patent expired June 27, 2015, the Board applies the Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005) (en banc) standard — confirmed in the institution decision. The single disputed term in the IPR was the "light input edge limitation": "the light input edge has a refractive surface that redirects the light output distribution of the light source more in the width direction as the light enters the panel member." Patent Owner argued for "more in the width direction than height direction"; Petitioner argued no such gloss should be imported. The Board, per Petitioner's reply, construed the phrase "in accordance with its ordinary and customary meaning" without the "than height direction" gloss. This construction is outcome-determinative for § 103, as shown in § 4.

POSITA. The parties' experts (Mr. Credelle for Petitioner; Mr. Werner for Patent Owner) illustrate the level of skill: a person with a degree in electrical/optical engineering or physics and several years of experience designing edge-lit light guides, backlight units (BLUs) and LCD display modules. On the record, a POSITA would (a) know that side-lit panels are lit by coupling discrete point sources into an input edge, (b) know that light-extracting surface features (disruptions, prismatic ridges, depressions) are used to defeat total internal reflection and out-couple light, and (c) know that reflectors (back/end/side) are used to reclaim stray light. Every claim limitation in the '816 patent sits squarely within that ordinary knowledge.

2. The applicable prior art window — a critical threshold point

Because the '816 claims carry a June 27, 1995 effective filing date (continuation of the 08/495,176 chain), the § 103 art must pre-date that date. This is important because the large "Patent Citations (170)" list the examiner assembled during the 2011‑era prosecution is dominated by post‑1995 references that are not prior art to these claims (they post-date the priority date and are not § 102(e) filings). Examples drawn from the record's citation list that fall outside the window include:

The genuine § 103 attack is therefore built on the pre‑1995 references actually invoked in the IPRs, plus the earlier Lumitex/Parker art. That art is:

A notable feature of this case: the primary reference, Pristash, is the same design family the '816 patent is built on. The '816 specification itself states the light sources "may be … any of the types disclosed in U.S. Pat. Nos. 4,897,771 and 5,005,108, assigned to the same assignee as the present application, the entire disclosures of which are incorporated herein by reference." In other words, the patentee (1) co-invented Pristash, (2) assigned it to the same company (Lumitex), and (3) affirmatively incorporated it as the starting point. For § 103 purposes, that incorporation is powerful evidence that a POSITA would treat Pristash as analogous art and as an obvious point of departure.

3. What each claim actually requires (element decomposition)

The previously generated summary recites the claims; I decompose them only as needed for the chart. Claim 1's limitations:

• [1a] at least one light source
• [1b] panel member with an input edge for receiving light + a light emitting surface
• [1c] a tray or housing having a cavity or recess in which the panel member is entirely received
• [1d] a pattern of light extracting deformities on/in at least one surface
• [1e] end edge reflectors and side edge reflectors
• [1f] an additional component overlying the panel member
• [1g] panel has greater width than height
• [1h] the input edge has a refractive surface that redirects the light distribution more in the width direction

Claims 2–4 are narrow placements/identifications:

• Claim 2: the end/side edge reflectors are on the panel's end/side edges.
• Claim 3: the end/side edge reflectors are on the tray/housing walls.
• Claim 4: the light source comprises one or more LEDs.

4. Combination argument A — Pristash alone (single-reference obviousness)

Pristash teaches the overwhelming majority of claim 1:

Why claim 1 would still be obvious over Pristash alone. Even without an express "tray," a POSITA reading Pristash's Fig. 8 sees a panel with back, end and side reflectors, i.e., a structure functionally enclosing the panel. Petitioner's Ground 2 argued a POSITA would find it obvious "to enclose the light guide of Pristash's Figure 1 within the complete set of back, end, and side reflectors disclosed in Pristash's Figure 8," to obtain "the well-known benefits of preventing light loss and providing necessary structural support for an LCD backlight assembly." This is the classic KSR "combining prior-art elements according to known methods to yield predictable results" rationale, and it is a within-a-single-reference combination, which further strengthens it (no cross-reference combinability problem at all). A POSITA would have a high expectation of success because the reflectors are disclosed for their ordinary function.

5. Combination argument B — Pristash + Suzawa (US RE 33,987)

Suzawa is used to cure the only express gap ([1c], and the claim‑3 reflector placement):

Motivation to combine. Both references are in the same field (edge-lit LCD backlighting); Pristash expressly recommends its illuminators for LCD backlighting, and Suzawa is an LCD backlight. The references address the same problem — light leakage and non-uniform illumination — and Suzawa's stated benefits (preventing light leakage, improving uniformity, increasing efficiency) supply an articulated reason to enclose Pristash's panel in Suzawa's reflective tray. Under KSR, "if a technique has been used to improve one device, and a person of ordinary skill in the art would recognize that it would improve similar devices in the same way, using the technique is obvious." The combination is a predictable integration of two known backlight components, and Patent Owner's own expert conceded such a combination was at least "possible" in the parallel proceedings in this family (Ex. 1032 at 283:15‑22, addressing the analogous Suzuki/Pristash pairing).

6. Combination argument C — Pristash + Tsunoda (the strongest § 103 case)

This pairing attacks both disputed limitations at once and is the most compelling § 103 theory in the record:

Motivation to combine. This is not a mere "art gallery" aggregation; the references teach the same solution to the same problem:

• Tsunoda's stated problem is bright/dark banding near discrete LEDs ("extremely bright … sections between adjacent light emitting diodes are comparatively dark," Tsunoda ¶¶[0011]‑[0012]), and its solution is to spread and reflect light across the width of the plate. Pristash's stated objective is "more efficient transmission of light" and control of the output distribution. These are the same objectives the '816 patent itself recites ("increased uniformity and higher light output … with lower power requirements," '816 col. 2).
• Pristash expressly contemplates LEDs, so substituting Tsunoda's LED source (claim 4) into Pristash — or vice-versa — is a simple substitution of one known element for another, a recognized KSR rationale.
• Because Tsunoda puts the light guide in a holder and uses reflective films, adding Tsunoda's housing to Pristash's panel is a use of a known technique (reflective enclosure) to improve a similar device in the same way, with a predictable result.

The decisive limitation [1h]. Under the Board's construction (ordinary meaning, without importing "than height direction"), Tsunoda's radial diffusion from depressions and notches across a plate whose width greatly exceeds its height meets [1h]. Petitioner's showing was that Tsunoda's isotropic source, entering a width‑greater‑than‑height plate, necessarily refracts/spreads more across the width. This is why the Board's construction choice is outcome‑determinative and why Combination C is the highest‑confidence § 103 theory in the file.

7. Combination argument D — the "LED + tray" family (Kisoo / Ciupke / Seraku)

For claim 4 (LEDs) and the tray limitation, the record supplies an independent, well‑supported combination:

• Pristash + Kisoo (JP 06-230378): Kisoo teaches a plurality of rectangular LEDs, each wider than tall, and a panel received within a tray. Pristash expressly suggests LEDs as an alternative source, making the substitution "a natural and predictable substitution to achieve a desired light shape." Kisoo's tray supplies [1c].
• Pristash + Seraku (JP 05-69732): Seraku teaches rectangular LEDs and a reflecting case/tray receiving the panel — a second, cumulative teaching of the tray limitation and the claim‑3 reflector-on-housing‑wall placement.
• Ciupke (US 5,461,547): microgroove light guide (deformities) + U‑shaped reflector shaping the source into a greater width than height distribution + a plurality of light sources; the combining rationale is the same (same field, same problem). Caveat: issued Oct 31, 1995 — confirm its § 102(e) filing date pre-dates the invention before relying on it as art.

These references establish that, as of 1995, LED sources, reflective trays/cases, and width‑shaped light distributions were individually known and routinely combined in backlight design — which defeats any argument that the claimed aggregation produced an unexpected result.

8. Dependent claims

Claim 2 — reflectors on the panel's own end/side edges. Met directly by Pristash Fig. 8 (edge reflectors 71 on the sides and 72 on the end of panel 62), and by Fig. 1's end reflector 22 and Fig. 4's end reflector 38. No additional combination is needed; claim 2 adds nothing beyond the primary reference.

Claim 3 — reflectors on the tray/housing walls. Met by Tsunoda's reflective holder, by Suzawa's reflective enclosing element, and by Seraku's reflecting case. This claim falls on the same combinations in § 5–7 because those combinations already place the reflectors on the housing.

Claim 4 — one or more LEDs. Met by Tsunoda (LEDs in depressions), Kisoo, Seraku, and expressly suggested by Pristash ("an LED"). The substitution of an LED for Pristash's arc lamp/bulb is the paradigm KSR "substitution of one known element for another," and the motivation is express (lower power, thinner packages) — matching the '816 patent's own stated goals.

9. Aggregate KSR rationales and reasonable expectation of success

Expectation of success is high: each combination merely deploys components for their stated and understood functions, with no unpredictable interaction between the tray reflector and the deformities pattern. Nothing in the references teaches away; to the contrary, Pristash's express suggestion of LEDs and lens-shaped input surfaces, and Suzawa/Seraku/Tsunoda's express disclosure of reflective housings, all point toward the claimed arrangement.

Secondary considerations. On the record available, the patent's ~1995–2015 life was marked by extensive assertion against LG, HP, RIM, ZTE, Huawei, BMW, Garmin, VW/Audi, T‑Mobile, LG Display/Vizio/ASUS, Dell, Acer, Amazon, etc. (see the Litigation Summary), which Patent Owner could cite as a nexus-worthy "industry praise/acceptance" signal. However, the litigation record also shows: (a) a district court indefiniteness ruling (§ 112(2)) on a claim term in the IDT family (Aug 26, 2014) — the Petitioners characterized the "more in the width direction" term as having been found indefinite (I flag that I could not confirm which term was held indefinite; the previously generated material references the "quite small" term, while Petitioner's reply points to the light-input-edge term); (b) most suits resolved by dismissal/settlement rather than by adjudicated validity; and (c) a PTAB Final Written Decision (Mar 15, 2017) recorded by third‑party databases as "Unpatentable." Given the settlement-heavy history, the objective-indicia record is weak and largely unproven with a nexus to the claimed combination.

10. Bottom line

• Claim 1 is vulnerable under § 103 in at least three independent ways: (A) Pristash's Fig. 1 + Fig. 8 (single-reference/within-reference combination), (B) Pristash + Suzawa (tray/housing), and (C) Pristash + Tsunoda, which is the strongest because it supplies both the tray and the width-spreading refractive input edge.
• Claim 2 is essentially anticipated in substance by Pristash's Fig. 8 reflectors.
• Claim 3 falls with Combinations B/C/D (reflectors on the tray walls).
• Claim 4 falls by express substitution of LEDs (Pristash express; Tsunoda/Kisoo/Seraku).
• The pivotal issue is construction of the "light input edge … more in the width direction" limitation. Under the Board's ordinary-meaning construction (no "than height direction" gloss), Tsunoda's radial, width-dominant spreading satisfies it and Combination C is strong; under Patent Owner's narrower proposed construction, the limitation becomes the principal battleground. The institution decision adopted the ordinary-meaning construction, which favors unpatentability.

11. Verification needed before this analysis is relied on

1. PAPER filings for IPR2015-01866, including the Order section of the Mar 17, 2016 Institution Decision — to confirm which grounds (Tsunoda § 102 only, or also the § 103 Pristash grounds) were instituted, and to read the Mar 15, 2017 Final Written Decision claim‑by‑claim. (DocketAlarm and the PTAB E2E system at ptacts.uspto.gov.)
2. Ciupke (US 5,461,547) filing date — confirm § 102(e) availability relative to June 27, 1995.
3. Suzawa (US RE 33,987) — confirm the underlying patent's date and § 102(b) status.
4. The district court's indefiniteness ruling (Aug 26, 2014) — identify precisely which claim term was held indefinite (the "quite small" term vs. the light-input-edge term), because it bears on the construction fight under § 103.
5. Primary sources for the Tsunoda/Pristash/Suzawa disclosures are the IPR exhibits (Ex. 1006 Tsunoda, Ex. 1007 Pristash, Ex. 1008 Suzawa) as filed in IPR2015-01866; my characterization above follows the Petition/Reply/Patent‑Owner‑Response summaries and should be checked against those exhibits directly.