Sun Patent Trust’s EP3852468, read from the defense side.
EP3852468 is the LTE DRX reporting patent in Sun Patent Trust's live UPC campaign against Vivo. This implementer-side analysis of EP3852468B1 shows where the mapping comes under pressure, how priority creates a squeeze, and what evidence to gather next.
A construction-led non-essentiality attack on the DRX Active Time mapping, with the patent owner’s likely counterposition and a net assessment.
A seven-limitation pre-priority squeeze showing which mapped features were already known, substantially known, or apparently added after priority.
Three lack-of-inventive-step leads and element-by-element claim charts of independent claims 1 and 9 against TS 36.321 v12.10.0.
Demonstration sample. The report is 100% AI-generated and illustrative only; it may contain errors, omissions or alternative interpretations. It is not legal advice, not a legal opinion and not a technical expert opinion, and no reliance should be placed on it for litigation, licensing, investment, product, compliance or other decisions. Patent and case facts on this page are drawn from public records cited below as of July 17, 2026.
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The patent at a glance
- Patent
- EP3852468B1 on Espacenet
- Title
- Deterministic UE behaviour for CSI/SRS reporting during DRX
- Owner
- Sun Patent Trust
- Earliest priority
- March 20, 2013 (via EP13160199)
- Standard analyzed
- TS 36.321 v12.10.0, compared with pre-priority TS 36.321 v11.2.0 for the squeeze analysis.
- Current enforcement
- Pending Paris Local Division action against Vivo group entities, filed April 2025 (ACT_18933/2025 / UPC_CFI_361/2025).
- Report posture
- Implementer-focused defense: non-admission, non-essentiality and invalidity read-out.
A live smartphone-OEM assertion
Public UPC records place EP3852468B1 in an active Paris Local Division campaign, not merely in a licensing portfolio. The litigation footprint matters because it connects the claim mapping to present commercial risk.
- Apr 2025 → pending
- Paris Local Division (ACT_18933/2025 / UPC_CFI_361/2025) — Sun Patent Trust asserts EP3852468B1 against Vivo Mobile Communication, Vivo Tech and Vivo Mobile Communication Iberia, seeking infringement relief and a conditional injunction alongside a request concerning FRAND licence terms.
- Parallel campaign
- A separate Paris action asserts EP3407524 in the same wider campaign. The cases show a coordinated smartphone SEP enforcement posture rather than an isolated patent notice.
- What it signals
- The patent is being tested against a handset manufacturer in a forum capable of granting cross-border relief. For LTE implementers, its commercial assertion risk is current and concrete.
One public-record finding, published in full
EP3852468B1 is already part of live UPC enforcement against a major smartphone OEM. The Paris action targets three Vivo entities and combines infringement relief with a conditional-injunction request and a FRAND-licence component. That makes the patent a current implementer-defense problem, not a theoretical essentiality exercise.
We publish that finding because it is verifiable against public court records. The technical defense remains gated: the construction analysis, seven-limitation squeeze, three invalidity leads, standard pinpoint citations, prior-art references and net assessments are all inside the report.
Inside the 17 pages
- Executive summary · p. 3
- Patent, owner, standard, posture and the public enforcement footprint against Vivo.
- Key findings · p. 4
- The defense routes in one page: the pre-priority squeeze and invalidity leads, with the specific evidence reserved for the report.
- Non-essentiality · p. 5
- A construction-focused attack on the mapped DRX Active Time behavior, with counterposition and net assessment.
- Priority squeeze · pp. 6–9
- Seven limitations classified as disclosed pre-priority, substantially known or apparently added after priority across independent claims 1 and 9.
- Invalidity · pp. 10–12
- Three lack-of-inventive-step leads. The specific pre-priority references and combination reasoning remain gated.
- Annex A · pp. 13–17
- Element-by-element baseline claim charts of independent claims 1 and 9 against TS 36.321 v12.10.0.
Frequently asked questions
What is EP3852468?
EP3852468B1, “Deterministic UE behaviour for CSI/SRS reporting during DRX”, is a European patent owned by Sun Patent Trust with an earliest priority date of March 20, 2013. Our EP3852468 analysis tests the patent against 3GPP TS 36.321 v12.10.0 from an implementer-side, non-admission posture.
Where is EP3852468 being enforced?
Public UPC records identify a pending infringement action filed in April 2025 at the Paris Local Division against Vivo Mobile Communication, Vivo Tech and Vivo Mobile Communication Iberia. Sun Patent Trust seeks infringement relief and a conditional injunction in a campaign that also includes a separate action on EP3407524.
What is in the full report, and what stays gated?
The 17-page PDF contains a construction-led non-essentiality attack, a seven-limitation pre-priority squeeze, three lack-of-inventive-step leads and claim charts for independent claims 1 and 9. The technical reasoning, standard pinpoint citations, net assessments and all specific prior-art references remain inside the gated report.
Is this report a legal opinion?
No. It is a demonstration sample of the ClaimsEvidence defense read-out, 100% AI-generated and illustrative only. It is not legal advice, not a legal opinion and not a technical expert opinion, and no reliance should be placed on it for litigation, licensing, investment, product, compliance or other decisions.