Sterlite Technologies wins Fujikura patent revocation 2026

The development and why it matters

Sterlite Technologies Ltd (STL) said a key patent cited by Japan’s Fujikura group in an overseas infringement dispute has been revoked in full by the European Patent Office (EPO). The company disclosed the update in an exchange filing, calling it a crucial decision for its optical fibre cable business. STL said the ruling effectively brings a formal end to the UK patent litigation linked to its Celesta cable family. The decision removes an important legal uncertainty around a product line that was at the centre of infringement proceedings. STL also stated that the EPO’s decision is non-appealable, which adds finality to the outcome. The matter had involved Fujikura Ltd and Fujikura Europe Ltd as opposing parties. STL said there is no settlement involved. It also said no financial claim is outstanding against STL in relation to the proceedings.

What the EPO Technical Board of Appeal decided

According to STL’s filing, Fujikura’s patent EP3796060 has been revoked in its entirety by the Technical Board of Appeal. STL described the decision as non-appealable, meaning the revocation is final at the EPO level. The patent had been central to the dispute and was cited in the infringement case brought in the UK. STL referenced its earlier disclosure about the litigation in a letter dated December 5, 2025. The company positioned the EPO outcome as the decisive legal development that closes the loop on the UK litigation connected to the disputed patent. The filing focuses on the revocation itself rather than detailing the underlying technical claims. Still, the implication is clear from the disclosure: the patent no longer stands, and therefore cannot support continuing infringement proceedings based on that right.

How it ends the UK litigation around Celesta cables

STL said the patent formed the basis of infringement proceedings initiated against it in the UK in relation to its Celesta cable family. With the patent revoked in full, STL said the UK patent litigation concerning Celesta is formally ended. For investors, the practical importance lies in legal clarity and reduced uncertainty on operational continuity for the specific product family. STL’s statement was direct and procedural, with no suggestion of compromise between the parties. The company emphasised that the outcome is linked to the specific Fujikura patent EP3796060. It did not claim broader resolution of any other potential disputes beyond what was described in the filing.

Who the parties were in the dispute

STL said the litigation involved Fujikura Ltd and Fujikura Europe Ltd as opposing parties. The dispute was anchored to Fujikura’s EP3796060 patent and its alleged relevance to STL’s Celesta cable family. The filings do not list additional counterparties or jurisdictions beyond the UK proceedings and the EPO appeal outcome. The company’s disclosures also focus on the legal status of the patent, rather than the commercial relationship, if any, between the companies. In regulatory communication, this framing typically reflects what is strictly material to the case outcome and the company’s potential liabilities. In this instance, STL has stated there is no financial claim outstanding against it connected to the proceedings.

What STL had disclosed earlier: split judgement reference

In its update, STL also referred to an earlier court outcome, stating that the Court had issued a split judgement. STL said the judgement held that its ultra-high-fibre-count cable does not infringe, while determining that low-fibre-count cables are infringing. The filing did not provide further operational detail on product categories beyond this distinction. This context matters because it shows the dispute had multiple strands before the EPO revocation brought finality to the patent’s status. It also indicates that the litigation had already produced findings on infringement for certain products at some stage. The new development, as communicated by STL, is that the legal foundation of the dispute has now been removed through revocation of the patent itself.

Cost recovery: what the company is pursuing now

After the favourable ruling, STL said it is actively pursuing recovery of legal defence costs incurred in the matter from Fujikura. The company did not disclose the amount of costs it plans to seek. STL also stated there is no settlement involved, which clarifies that the matter was not resolved through negotiated terms. In addition, STL said no financial claim is outstanding against it in relation to the proceedings. Together, these points suggest STL’s next legal step is limited to cost recovery rather than any remaining damages exposure. However, the filing does not describe timelines or procedural steps for pursuing those costs.

Why a non-appealable revocation changes the risk profile

A non-appealable revocation provides legal certainty because it prevents a fresh appeal on the same patent’s validity within the EPO framework. STL highlighted this finality explicitly. In patent disputes, a final validity outcome can be more consequential than interim findings because it determines whether the asserted right exists at all. STL’s statement that the UK litigation is formally ended reflects how closely the UK case was tied to EP3796060. For STL, the absence of any outstanding financial claim connected to the proceedings reduces the immediate risk of litigation-linked payouts. The company also indicated it remains committed to protecting and developing its technologies, signalling that it views intellectual property as a continuing strategic area.

Market and investor lens: what is known from the disclosures

STL’s filing is largely legal and procedural, so it does not quantify any impact on sales, orders, or guidance. It does, however, remove a specific legal overhang tied to a named product family. Investors typically monitor such disclosures for three practical factors: exposure to injunction risk, exposure to damages, and the cost of ongoing legal defence. STL addressed part of this by stating there is no financial claim outstanding against it and by indicating the case is formally ended. The company’s stated intention to recover defence costs also suggests it views the outcome as clearly in its favour. Beyond these points, no stock movement data or operational changes were provided in the supplied material.

Key facts at a glance

What to watch next

The next update investors may look for is whether STL is able to recover legal defence costs, and whether any amount is disclosed later. Since STL has stated the EPO decision is non-appealable, the focus shifts from validity to post-case procedural matters like costs. Market participants may also track whether STL provides any additional commentary on product shipments, customer conversations, or compliance steps linked to the now-ended UK litigation. Any further filings could clarify how cost recovery is being pursued and in which forum. For now, the company’s disclosure is limited to the revocation, the closure of the UK litigation, and the absence of any outstanding claim against it.

Conclusion

STL said the EPO’s Technical Board of Appeal revoked Fujikura’s EP3796060 patent in full, in a decision that cannot be appealed. The company said this formally ends the UK patent litigation concerning its Celesta cable family. STL also stated there is no settlement and no financial claim outstanding against it related to the proceedings. The next concrete milestone will be progress on STL’s stated effort to recover legal defence costs from Fujikura.