Invalidity dossier
US 5642337
Added 9/21/2026, 9:26:47 AM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 5,642,337
Title: Network with optical mass storage devices
Patent number: US 5,642,337 A
Inventors: Orhun Oskay, Sanjay Kapoor, Phillip Hiroshige
Assignees: Sony Corp; Sony Electronics Inc (original and current assignee per the source listing)
Key dates:
- Priority date: 1995-03-14
- Application number: US08/709,668; filing date: 1996-09-09
- Publication/grant date: 1997-06-24
- Anticipated expiration: 2015-03-14; status: Expired – Lifetime
Purpose: To let a user access more optical mass-storage capacity than a single jukebox (roughly 26 GB in a 20-disk example) can provide, without the cost and lost investment of repeatedly replacing jukeboxes, and without the address and cable-length limits of SCSI (8 addressable peripherals; each jukebox using three addresses; cables not to exceed 3 meters). The stated aim is convenient access to data across multiple jukeboxes, avoiding peripheral switching.
Plain-language scope: A mass storage system has a "master" jukebox with a local computer, plus multiple "slave" jukeboxes coupled over a network. All jukeboxes operate in SCSI protocol. The master's local computer includes a CPU, an initiator SCSI controller, a network controller, and a hard disk holding a jukebox file system. On a data request, the CPU determines the jukebox, disk, and file; if the data is on the master, it sends SCSI commands via the initiator controller to the master's slave SCSI controller; if on another jukebox, it encodes the SCSI commands per the network protocol and transmits them via the network controller. Each slave jukebox has a firmware interface unit that intercepts network packets containing encoded SCSI commands, decodes them, forwards them to its jukebox, receives retrieved data, re-encodes it into network packets, and returns it to the computer, which forwards it to the requester. The interface unit includes a CPU, EPROM, DRAM, an initiator SCSI controller, and a network controller.
Source: https://patents.google.com/patent/US5642337/en
What the excerpt does not establish: It is excerpted and ends mid-sentence ("an initiator SCSI controller for c…"), so the full specification and all claims are not available here. It provides no claim text, no prior-art references, no litigation, ownership-transfer, or validity information. Dates, assignees, and legal status are as listed by the source and are expressly assumptions, not legal conclusions.
Generated 10/1/2026, 10:02:23 PM
Cases on file (0)
Specific litigation cases in our database that name US patent 5642337. The free-form analysis below may also discuss cases beyond this list.
No cases on file mention this patent. Upload a CSV or add a case manually in Admin → Manage litigation cases.
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.