Invalidity dossier
US 5385839
Transfer vectors and microorganisms containing human cytomegalovirus immediate-early promoter regulatory DNA sequence
Current assignee: University of Iowa Research Foundation
Added 9/23/2026, 9:57:41 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 — US 5,385,839
Title: Transfer vectors and microorganisms containing human cytomegalovirus immediate-early promoter regulatory DNA sequence
Assignee: University of Iowa Research Foundation (UIRF), the original assignee.
Inventor: Mark F. Stinski.
Key dates (as listed): Priority date 1985-01-30; application US07/900,056 filed 1992-06-17; granted/published 1995-01-31; anticipated expiration 2012-01-31; status listed as "Expired - Lifetime."
Purpose: The invention concerns cloning a deoxynucleotide sequence carrying regulatory signals preferentially recognized by human cell factors involved in RNA polymerase II transcription. That sequence—the HCMV promoter-regulatory region (also described as an enhancer)—is used to enhance expression of an adjacent gene in eukaryotic cells of human origin. HCMV is human cytomegalovirus; "IE" means immediate early.
Plain-language scope (per the excerpt): Viral DNA is purified and digested with the restriction endonuclease XbaI; XbaI fragments are cloned into plasmid pACYC184. The HCMV XbaIE region is identified as highly transcribed in human cells immediately after infection—more than 88% of viral RNA originates from the long unique component between 0.660 and 0.751 map units (Towne strain). The major IE gene lies between 0.739 and 0.751 map units. XbaIE DNA is digested with PstI and cloned into plasmid pKH47, yielding clone pXEP22, which contains a strong promoter-regulatory region but retains extraneous flanking DNA. pXEP22 is digested with Sau3A to isolate clone pIEPR12, containing approximately 760 base pairs of HCMV DNA inserted into vector plasmid pAT153—this region holds the promoter and regulatory sequence for efficient transcription in human cells. The excerpt's "Definitions" section also explains general concepts: transfer vectors, plasmids, transformation, restriction endonucleases, expression, and control regions.
What the excerpt does not establish: It contains no claims text, no complete sequence listing, no host-cell or microorganism examples, no legal conclusions, and no information on litigation, ownership transfers, validity, or prior art. It is an excerpt only; omitted text should be consulted.
Generated 10/1/2026, 9:33:55 PM
Cases on file (0)
Specific litigation cases in our database that name US patent 5385839. 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.