Invalidity dossier
US 8797198
Linearized optical digital-to-analog modulator
Current assignee: Ramot at Tel Aviv University Ltd
Added 9/23/2026, 11:01:57 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US8797198B2
Title: Linearized optical digital-to-analog modulator
Patent number: US8797198B2
Application number: US13/280,371
Inventor(s): Yossef Ehrlichman, Ofer Amrani, Shlomo Ruschin
Original/current assignee (as listed): Ramot at Tel Aviv University Ltd.
Priority date (listed as an assumption): 2007-06-13
Filing date: 2011-10-25
Publication date: 2014-08-05 (application published as US20120081245A1 on 2012-04-05)
Legal status (as listed; not a legal conclusion): Active, adjusted expiration 2029-03-12
Source: https://patents.google.com/patent/[US8797198](/patent/US8797198)/en
Purpose and plain-language scope (from supplied text only):
The patent concerns an optical digital-to-analog modulator that is "linearized." The supplied excerpt identifies prior-art keywords — modulator, actuating, electrodes, electrode, optical signal — indicating the subject matter involves an optical modulator whose electrodes are actuated to act on an optical signal. Classifications place it in optical digital-to-analog conversion (G02F7/00), optical modulation via interference in waveguide structures (G02F1/225), digital intensity/amplitude modulation (H04B10/541), and digital-to-analog converters (H03M1/66). The title implies the modulator converts a digital input into an analog optical output while improving linearity. The excerpt does not contain the claims or detailed description, so the specific structural arrangement, number of electrodes, actuation scheme, and linearization technique are not established here.
What the excerpt does not establish:
The excerpt does not supply the claims, written description, drawings, or prosecution history. It does not establish the actual scope of any claim, the specific linearization mechanism, or the number/configuration of electrodes beyond the keyword list. The priority date, legal status, and expiration are expressly flagged in the source as assumptions, not legal conclusions. The listed litigation, PTAB, and reassignment entries (including the security-interest assignment to PBLM RTAU LLC) appear in the source but are outside this overview's scope per the stated instructions and are not analyzed here. No validity, enforceability, or prior-art conclusions are drawn.
Generated 10/1/2026, 9:32:59 PM
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Litigation summary
Past and pending lawsuits — plaintiffs, defendants, jurisdictions, outcomes, and notable rulings.
Proceedings on file (0)
All PTAB activity →AIA trial proceedings (IPR / PGR / CBM) filed at the USPTO Patent Trial and Appeal Board against this patent. Sourced from the USPTO Open Data Portal and refreshed every six hours; each proceeding number deep-links to the PTAB E2E docket.
No PTAB proceedings on file. This patent has not been challenged via IPR, PGR, or CBM. The absence is itself a signal — well-asserted patents eventually attract IPRs. The LLM analysis below may surface filings the ODP feed hasn’t indexed yet.
PTAB challenges
AIA trial proceedings at the USPTO Patent Trial and Appeal Board — IPR, PGR, and CBM. Petitioners, judge panels, claim-level invalidation outcomes from Final Written Decisions, and Federal Circuit appeals. The single most important defensive datapoint after litigation history.
Assignment history
Inventors, original assignee, and the chain of ownership recorded with the USPTO — including the correspondent attorney who recorded each assignment, since shell-LLC chains often share one repeat-player attorney even when the entity names look unrelated. Surfaces NPE / patent-troll patterns: shell-entity transfers, known asserters in the chain, repeat correspondent fingerprints, pre-litigation assignments, and bankruptcy fire-sales.
Prior art
Earlier patents, publications, and products that may anticipate or render the claims unpatentable.
Obviousness
Combinations of prior art that suggest the claimed invention would have been obvious under 35 U.S.C. § 103.
Extensions
Patent term adjustments, term extensions, continuations, divisionals, family members, and expiration dates.
Derivative works
Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.