Invalidity dossier
US 4738852
Feedstuff for swine
Current assignee: Resonac Holdings Corp
Added 9/23/2026, 12:14:42 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
US 4,738,852 — "Feedstuff for Swine" (Patent Overview)
Title: Feedstuff for swine
Patent number: US 4,738,852 A
Inventors: Nobuhiro Watanabe, Tadao Takase, Juichi Kasai
Original assignee: Showa Denko KK. The source lists a current assignee, Resonac Holdings Corp, with the caveat that listed assignees may be inaccurate and that Google has not performed a legal analysis.
Application number: US06/757,773 | Filed: 1985-07-23 | Granted/published: 1988-04-19
Priority: Two Japanese priority applications — JP57083981A and JP57084914A, both dated 1982-05-20 and 1982-05-21 respectively (Google notes priority dates are assumptions, not legal conclusions). This application is therefore a later-filed case claiming earlier Japanese priority.
Legal status: Expired – Fee Related; anticipated expiration listed as 2005-04-19.
Purpose and plain-language scope: The patent relates to swine feed. The indexed terms indicate a tryptophan-containing feedstuff, with tryptophan and its salts appearing in the claims, abstract and description. The abstract mentions milk constituents; other indexed concepts include body weight, weight gain, estrus, lactation, parturition, essential amino acids, crude protein, vitamins and minerals. This suggests an additive or feed formulation intended to supply tryptophan to pigs, potentially affecting body-weight gain and reproductive performance. However, because the excerpt contains no claim language or full description text, that reading is inferred from indexed keyword counts, not from explicit wording.
Source: https://patents.google.com/patent/US4738852/en (fetched 2026-09-23).
What the excerpt does not establish:
- The actual text of any claim, including tryptophan amounts, dosage ranges, or feed percentages.
- The specific swine classes addressed (e.g., sows, piglets, growing pigs) or whether estrus/lactation effects are claimed or merely mentioned.
- Whether "body weight" relates to the animal or to feed weight.
- Any prior-art references, prosecution history, or the Japanese priority documents' contents.
- Any litigation, ownership transfer, validity or enforceability conclusion — none was researched or is asserted here.
Excerpt only; the omitted text should be consulted in the source before relying on these inferences.
Generated 10/1/2026, 9:53:45 PM
Cases on file (0)
Specific litigation cases in our database that name US patent 4738852. The free-form analysis below may also discuss cases beyond this list.
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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.