Y-OCTA: The LG Display Claim That Outlived Samsung Prior Art

Of the 7 patents LG Display asserted against Tianma, the only one Tianma tried to invalidate at the US Patent Office was a Y-OCTA structure patent. That patent was granted on the two lines left after Samsung prior art stripped away the rest, and when Tianma came back armed with Samsung documents again, its petition never reached a technical hearing. What shut the door was an ownership structure that brought AVIC in back in 2011.

1. Overview

1.1 Seven patents, and one of them

On June 13, 2025, LG Display sued China’s Tianma in the US District Court for the Eastern District of Texas. The complaint asserted 7 patents: 4 on LCD and 3 on OLED. The 4 LCD patents targeted panels in vehicle instrument clusters such as the Chevrolet Equinox EV and in the Motorola Moto G Stylus; the 3 OLED patents targeted panels in the Motorola edge+ and the Xiaomi 13T. The damages theory in the complaint also rested on automotive LCD. LG wrote that the two companies had gone head to head in 13 automotive panel bids between July 2022 and December 2024.

Yet of those 7 patents, Tianma took only one to the US Patent Office to challenge its validity. It was a patent (US11251394B2, hereafter ‘394) on the structure that places touch electrodes on top of thin-film encapsulation — the very structure Samsung Display first mass-produced in 2016 and the industry calls Y-OCTA.

In February 2026, the Director of the US Patent Office denied Tianma’s petition without looking at the technology, and in March explained why. Two months later, the two companies withdrew every suit they had pending against each other in the US.

Why that one patent, and why was it stopped at the door? This piece traces the path back through the patent texts and the litigation record. The conclusion comes first.

The Y-OCTA structure patent LG aimed at Tianma was granted on the two lines left after Samsung’s earlier filings had stripped away most of it. Tianma tried to break that patent with Samsung documents once again, but never got a hearing. What shut the door was an ownership structure that brought AVIC in back in 2011 — and that same stake was also the starting point of the two companies’ 10 years of license negotiations.

1.2 Scope of analysis

1.3 Terminology

2. The principle is Y-OCTA, and Samsung built it and claimed it first

The first to claim “placing touch on top of the encapsulation thin film” was Samsung Mobile Display, in May 2007. That is 9 years before Samsung Display first mass-produced the structure in 2016.

2.1 Drop the film, build directly on the encapsulation

Earlier OLED phones built the touch function on a separate film and laminated it onto the panel. Y-OCTA eliminates that film and its adhesive layer, and forms metal-mesh electrodes — metal lines laid out like a net — directly on the thin-film encapsulation by deposition and etching. Fewer layers make it thinner and better suited to folding screens.

Samsung Display first put this structure into the Galaxy Note7 in 2016 (KIPOST). The industry headed toward the same goal under different names: LG Display’s TOE and BOE’s FMLOC.

Figure 1. Add-on touch versus Y-OCTA. The touch film and adhesive layer drop out, and the electrodes sit directly on the encapsulation. Layer thicknesses are not to scale

2.2 The earliest claim dates to 2007

Kodak stands at the front of touch-on-encapsulation. A 2002 Kodak patent (US6879319B2) formed a touch screen on the outside of the glass cover sealing the OLED. The encapsulation was a glass cap, not a thin film.

The first claim to move to thin-film encapsulation is a Korean patent (KR100873080B1) filed by Samsung Mobile Display on May 10, 2007.

This first claim is not today’s capacitive type but a resistive type, in which pressing brings two electrodes into contact. Still, it was here that the ground of “forming touch electrodes on a panel sealed with a thin film” was first staked out.

The following year Samsung filed two more. The August 2008 filing (US8237354B2) placed a first touch conductive layer directly on the encapsulation thin film, and the November 2008 filing (US9292118B2) laid a planarization layer over the encapsulation thin films and placed a touch conductive layer on that flat surface.

In China, the Visionox group (Kunshan New Flat Panel and Go-Visionox) stacked an encapsulation layer, a touch layer, and an encapsulation layer in sequence in a December 2013 filing (US10061416B2). Within the range this piece confirmed, LG Display first claimed touch on an encapsulation layer in September 2015 (Section 3).

Figure 2. Priority dates of documents claiming "touch on encapsulation," with mass-production and grant dates. Only claims whose original text was checked for this piece are shown

2.3 A claim with a 2008 date, granted in 2025

Samsung’s November 2008 filing did not end there. It carried on through continuation applications to 9 grants in the US alone, and the last of them (US12386474B2) was granted on August 12, 2025. Its priority date is still November 28, 2008.

A touch sensor placed directly on the encapsulation without an adhesive layer — that is the gist of Y-OCTA. Google Patents estimates its expiration at April 2029. Samsung is still filing new claims in the 2020s, under a 2008 date, on a structure it mass-produced in 2016.

2.4 By the numbers

Among patents filed in the US through 2015 and granted, Samsung has 48 and LG 4 — 12 times as many. In 2016-17 the gap narrowed to 50 versus 38, around the time Samsung mass-produced Y-OCTA and LG came in. Counted with the same search query, granted patents from Chinese companies number 186 for BOE, 98 for CSOT, 58 for Tianma, and 20 for Visionox.

3. LG came in in 2015

The first filing in LG Display’s own list of 1,603 TOE patents, submitted to the tribunal, is from September 2015. And where LG’s TOE patents placed their novelty was not “touch on encapsulation” itself but the layout, routing, and layer structure on top of it.

3.1 The starting point LG wrote down itself

LG Display submitted an exhibit to the PTAB titled “LG Display TOE Patent List” (EX2012). It lists 1,603 patents across 10 countries: 480 in the US, 397 in Korea, 317 in China, and 96 at the European Patent Office, in that order. 1,071 of them are granted.

The first line of the list is a Korean application filed on September 24, 2015 (10-2015-0135110). It is the only 2015 filing; the count grows to 66 in 2016 and 176 in 2017, and runs at 150-235 per year after that.

The earliest LG touch-on-encapsulation claim this piece found at the US Patent Office dates to the same month. A US patent (US9947727B2) with a Korean priority date of September 7, 2015 put “a touch electrode array on the encapsulation layer” into claim 1. That patent is not on LG’s list. Either way, LG’s starting point is September 2015 — 8 years after Samsung’s first claim.

3.2 Where LG’s TOE placed its novelty

If the ground of the principle was already taken, what did the latecomer claim? We picked 6 LG US granted patents from each of four US filing-year bands (2016-17, 2018-19, 2020-21, 2022~), 24 in total, and read claim 1.

Of the 24, 16 had “touch on encapsulation” as an element of claim 1. The other 8 were caught by the search through a claim other than claim 1. We then sorted the 16 by what they newly limited in the characterizing portion after “wherein.”

Among the 16, no claim put forward “placing touch on the encapsulation” itself as the novelty. All of them took touch on encapsulation as a given and claimed what goes where on top of it. The asserted patent in Section 4 also spans the first category (layout overlapping the bank) and the second (routing along the side of the encapsulation).

Figure 3. Characterizing portions of claim 1 in the 16-patent LG Display sample. Claims placing the novelty in "touch on encapsulation" itself: 0

4. ‘394: the two lines Samsung prior art left standing

The US examiner found that a single 2015 Samsung Display filing already contained every claim of LG’s application. What survived were two lines — “the bridge overlaps the bank” and “the routing runs along the side surface of the encapsulation” — and LG rewrote those two as independent claims to get the patent granted.

4.1 History of the asserted patent

The priority date of ‘394 is June 30, 2016 (Korea 10-2016-0083006). Two US patents claiming priority to the same Korean application (US10505142B2, US10727436B2) were granted first; ‘394 was filed again in June 2020 and granted on February 15, 2022. The complaint used claim 1 of this patent to target the Tianma OLED panel in the Motorola edge+.

4.2 What the examiner saw

Tianma summarized this prosecution history in its IPR petition.

Kang651 is a Samsung Display application with a September 30, 2015 priority date (US20170090651A1). The examiner found that this one document had everything: touch electrodes, bridges, two levels of conductive lines, the insulating film between them, the encapsulation unit, and touch pads. The two surviving dependent claims are these.

Granted claim 1 of ‘394 lays out in sequence the touch sensor on the encapsulation unit, the bridges, the two levels of conductive lines and insulating film, and the bank exposing the anode, then attaches this one line at the end.

Figure 4. The two lines that survived in '394. Only the two colored areas were not found by the examiner in the Samsung document. Redrawn from the patent's FIG. 2

4.3 Why put the bridge on the bank

The specification gives the reason for that one line.

A bridge is a span that crosses to another layer to connect touch electrodes. Whether metal or transparent electrode, it blocks some light. Placing this span on the dam that emits no light — the bank — keeps it from cutting screen brightness. As pixels get denser, banks get narrower, and the span more easily sticks out past the dam.

4.4 Samsung documents LG listed itself

‘394 has 30 prior patents of record. Of those, 12 are Samsung documents (including Samsung Mobile Display). LG itself listed 8 of them when filing, and the examiner added 4. Those LG listed itself include Samsung’s November 2008 filing from Section 2 (US9292118B2) and a Chinese filing by Samsung Mobile Display from August of the same year (CN101661949A). One of the 4 the examiner added is Kang651 from Section 4.2.

LG knew the Samsung documents holding the principle, and claimed the ground that avoided them.

5. Why Tianma couldn’t defend with prior art

Of the 5 documents Tianma relied on to break ‘394, 3 name Samsung on their face and 1 more appears to be from the Samsung family. But the stage on which to argue them never opened. The Director of the US Patent Office established, for the first time, the rule that “a foreign government cannot petition for IPR,” and shut the door on the grounds of Tianma’s shareholder AVIC.

5.1 The weapons were Samsung’s too

Defending with prior art means showing that “the invention already existed.” But two lines remained that the examiner had kept alive even after seeing Samsung documents. So Tianma chose a combination argument — not “it is all in one document” but “combining this and that would have made it obvious.” The petition filed on October 23, 2025 (IPR2025-01579) had five grounds.

Of the five documents, three list Samsung as the applicant on their face. Jang513’s publication lists no applicant (assignee). With an inventor based in Yongin and a subject of “mesh-type sensing electrodes on an encapsulation thin film,” it appears to be a Samsung-family document, but this piece could not confirm that. The petition also submitted Kang651, which the examiner had used, as a separate exhibit. Kim481’s abstract opens with “an integrated touch screen panel formed directly on an encapsulation thin film.” The material used to attack LG’s patent was also Samsung’s prior art.

5.2 The Patent Office door and the court door

In the US there are two ways to challenge the validity of a granted patent (general law).

That is why defendants look to IPR first. And on December 30, 2025, LG Display filed a request for “discretionary denial” asking that this first door be shut (Paper 7).

5.3 “An issue of first impression”

Patent Office Director John A. Squires denied institution on February 18, 2026 (Paper 11), and on March 18 issued a decision giving the reasons (Paper 12). The Patent Office announced the same day that it had designated the decision as precedential.

The decision itself describes this as an issue being addressed for the first time.

In Return Mail in 2019, the US Supreme Court held that a US federal agency is not a “person” under the patent statute and therefore cannot petition for IPR. The Director extended that to foreign governments.

Then came the facts. LG pointed out that Tianma’s own court disclosures listed AVIC Innovation as a shareholder holding “10% or more” of Tianma, and that AVIC (Aviation Industry Corporation of China) is owned by the Chinese government and on the US Commerce Department’s export control list. The decision assessed Tianma’s rebuttal this way.

The decision also recounted LG’s argument that, treating the export-controlled companies and Tianma as a single bloc, they would rank in the top 10 for IPR petitions filed in 2019-2024. The decision did not address the technical content of ‘394 in a single line.

5.4 What changed was the law, not Tianma

A PTAB search for the party name “Tianma” returns 11 cases. Of those, 9 are IPRs Tianma filed against Japan Display (JDI) patents.

AVIC had been inside the ownership structure on Tianma’s side since 2011 (Section 6). With that stake in place, Tianma filed IPRs in 2016 and 2021, and the two 2016 cases were heard to the end. What changed in 2026 was not Tianma but the Patent Office’s law. LG’s request for discretionary denial pinpointed exactly the place where that new rule would first be applied.

Figure 5. IPRs Tianma filed at the US PTAB. The AVIC stake was the same from 2011 on, and the door closed in 2026

LG, too, filed a post-grant review (PGR) against a Tianma patent (US12,293,691) in February 2026. It appears related to the countersuit Tianma filed in the Western District of Texas in December 2025, but the original complaint was not checked. This petition ended in a settlement in June.

6. 10 years of negotiation, from LCD to OLED

The AVIC stake that blocked the 2026 IPR was already spelled out in a 2011 letter from Tianma’s side to LG. The two companies’ negotiations began with an LCD license and only moved to OLED in 2021.

Below is the history LG Display presented in its complaint (paragraphs 45-75) and in its PTAB exhibits.

The 2015 and 2020 letters covered TN and IPS LCD, in-cell touch, and LTPS patents. The words Y-OCTA structure or TOE never appear even once in either letter. The ‘394 family is first confirmed on the negotiating table in the October 2021 “list of patents related to mobile OLED products.” ‘394 itself was granted three and a half months after that.

The starting point of the negotiation and the outcome of the IPR are tied to the same ownership structure. When NEC’s stake passed to AVIC in 2011, the 2001 license was cut off — and because of that very stake, Tianma was turned away at the Patent Office door in 2026.

7. Why doesn’t Samsung sue LG?

If Samsung holds the principle, what about LG’s TOE panels? This is as far as public materials answer that question.

The two companies fought once in a big way. According to LG Display’s annual report, in September 2012 LG sued Samsung Display and Samsung Electronics for OLED patent infringement, Samsung Display sued LG for leaking OLED trade secrets, and in December Samsung Display sued LG on LCD patents. Each side also filed invalidity actions against the other’s patents. In February 2013 they agreed in principle under government mediation, and in September 2013 withdrew all suits and invalidity actions.

After that, foreign media citing Korean reports said that cross-license talks broke down in June 2014 — Samsung wanted one and LG was not interested. The cross-license partners LG Display names in its annual report are Hitachi, HannStar, Hydis, NEC, and AUO; Samsung is not among them. However, the report also says it “has entered into such agreements with other third parties,” so it cannot be concluded that no license exists.

Today both companies point their blades not at each other but at China. Samsung Display took BOE-related OLED panels to the US International Trade Commission in December 2022 and settled in November 2025. LG sued Tianma. In 2025 there were also reports that LG transferred LCD patents to Samsung Display, assisting Samsung’s suits against BOE and CSOT.

8. What this analysis does not say

• Settlement terms. The court record shows only the joint dismissal and closure. Who paid whom and how much has not been disclosed
• Whether Tianma’s panels actually infringed ‘394. The court closed the case before ruling. The Patent Office did not look at the technology either
• Any current license between Samsung and LG. It cannot be confirmed from disclosures
• The technical content of the other 6 asserted patents. This piece noted only their titles and the products they targeted
• Representativeness of the LG sample. The 24 patents are the most recently published in each band, and Samsung patents were not classified the same way
• The path from Samsung’s first claim to mass-production technology. The 2007 first claim is resistive. Which patent the 2016 Y-OCTA practiced cannot be determined from patent documents alone
• The other side of the negotiation story. Section 6 is LG’s account

9. Conclusion

The idea of putting touch on top of the encapsulation film was claimed first by Samsung in 2007 and mass-produced first by Samsung in 2016. A Samsung-family patent bearing a 2008 date was newly granted as recently as 2025, on “a touch sensor without an adhesive layer.”

LG Display entered the field in September 2015, and instead of the principle claimed the layout, routing, and layer structure on top of it in more than 1,600 patents. ‘394, aimed at Tianma, was one such patent. The examiner stripped away everything else with a single Samsung document and left only “the bridge overlaps the bank” and “the routing runs along the side surface of the encapsulation.”

Tianma tried to break those two lines with Samsung documents again. But the US Patent Office shut the door before looking at the technology, with a rule it established for the first time. It was the same door Tianma had walked through against JDI in 2016 and 2021. What changed was not the AVIC stake, unchanged since 2011, but the law that reads that stake.

This decision has been designated precedential. Any panel maker with Chinese state ownership that wants to challenge a Korean patent by IPR in the US will have to pass the same question first. In this lawsuit, the place for a technical fight never opened — and had it opened, the documents laid on that table would have been Samsung’s.