US 5880858

I'll search for this patent across the requested sources.

Let me check for litigation and any 2026 CAFC activity.

One more targeted check for any Federal Circuit activity and current status.

US Patent 5,880,858 (US5880858A) — Summary

Sources consulted: Google Patents (which mirrors the USPTO full-text record), uspto.report (USPTO grant data), the Unified Patents patent portal, and USPTO PTAB (PTACTS) filings surfaced via search. I found no Federal Circuit 2026 docket activity tied to this patent number.

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Bibliographic data

Note on discrepancies (interpreted literally, not auto-corrected):

• Google Patents and uspto.report give the filing date as 1997-12-31 and issue date as 1999-03-09. The Unified Patents portal instead lists priority date 1997-12-30 and grant date 1999-03-08. These are a one-day offset, likely a time-zone/record-keeping artifact; the authoritative USPTO-derived text (Google Patents) supports 1997-12-31 / 1999-03-09.
• The assignee chain in the assignment records (2020-02-19 to Intellectual Ventures Assets 161 LLC, effective 2019-11-26) and the "current assignee" listing both point to IV; the ownership has moved through Mustek → Transpacific Optics LLC → IV.

Abstract (verbatim)

"A method of auto-cropping images appropriate for scanners is disclosed, that features use of the image-division method for carrying out auto-cropping. According to the method, the images of the objects after pre-scanning can be auto-cropped, and therefore do not require further manual operation. The interference due to the background color of the cover and other redundant images can also be reduced. Furthermore, the present invention is also appropriate for scanning positive and negative films, and films are disposed on frames can be scanned properly."

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Plain-language overview of the independent claims

The patent has two independent claims: claim 1 and claim 5 (claims 2–4 depend from 1; claims 6–9 depend from 5).

Claim 1 — Core auto-cropping method (general scanners).
A method that automatically finds and cuts out scanned objects from a pre-scanned preview image, without a user drawing crop boxes:

• (a) Take the pre-scanned image and run it through an "image-division method" that computes at least a low threshold and a high threshold (adaptive, rather than a fixed threshold).
• (b) For each horizontal row, count how many pixels exceed the low threshold — this count is the row's "dot-intension number." Compare each row's count to a limit; rows exceeding the limit are cropped, splitting the image into several regions.
• (c) Within each region, do the same column-by-column vertically (count pixels above the low threshold, compare to the limit), further splitting each region into cropped sub-regions.
• (d) Iterate steps (b) and (c), alternating horizontal and vertical passes, until no further division is possible.

In effect: recursively bisect the image along rows/columns that contain "content," converging on bounding boxes around the individual objects.

Claim 5 — Auto-cropping for films, with or without frames.
A variant for film scanning (slides/negatives), which must first determine whether the film is mounted in a frame:

• (I) Confirm the film type and detect frames. If a frame is detected, proceed to step (II).
• (II) Preprocess the pre-scanned image according to film type, then:
  • 2a–2d — the same adaptive-threshold, row/column, iterative cropping process as claim 1 (obtain low/high thresholds; crop rows then columns; iterate to convergence);
  • 2e — an occupancy check: for each cropped region, count pixels exceeding the high threshold. If that count exceeds a set proportion of the region's total pixels, the region is deemed to contain no film and is discarded — so only actually-occupied film positions are kept.
• Fallback: If no frame is detected in step (I), steps 2a–2d are still applied to crop the film regions properly.

Dependent-claim highlights (context)

• Claim 2 / claim 7: Detail the "image-division method" — this is a k-means-style iterative clustering routine. Initial central characteristic values a₁…aₙ are chosen; each pixel's characteristic value (e.g., average of color values) is assigned to the nearest centroid; centroids are replaced by set means and the process iterates until convergence (e.g., |Tᵢ − aᵢ| within a tolerance such as 1). The minimal and maximal converged means become the low and high thresholds. Example seed values given: a₁=3, a₂=250.
• Claim 3: Cover-handling — pre-scan and store a background image with no objects; detect whether the cover is closed; if closed, subtract the background from the pre-scan before cropping (removes cover background color and stray "connection lines").
• Claim 4: Masking/recovery — mask out a margin strip, crop the unmasked portion, then expand the crop regions into the masked strip as "recovery regions" and re-process them to recover objects partly hidden under the mask (mask width examples: 18 px high-res, 9 px low-res).
• Claim 6: Frame-detection sub-steps — obtain thresholds, crop rows exceeding the limit and record row numbers, convert the known film-holder size (e.g., 3.6 cm) into pixel dots via pc = (3.6/2.54) × prescan_dpi, and declare a frame detected if at least two recorded row numbers fall within a tolerance (e.g., sn = 3) of that pixel dot count.
• Claims 8 & 9: Reversal (complement) operations — negative film images are reversed before frame detection and/or before cropping; positive film images are processed without reversal.

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Litigation / docket findings

• I searched for CAFC 2026 dockets and for Federal Circuit appeals referencing 5,880,858: no results were returned. Given the patent's expired status (anticipated expiration Dec. 31, 2017), current appellate activity is unlikely, and I have no authoritative evidence of any 2026 Federal Circuit docket involving this patent.
• The only litigation context surfaced relates to the Intellectual Ventures / Transpacific monetization ecosystem generally (e.g., an IV declaratory-judgment matter referencing other IV patents such as the '785, '722, '582, '080, and '894 patents) — not to 5,880,858 specifically. I would not attribute any of those cases to this patent.
• Notable forward citations include same-family Mustek/Transpacific follow-on patents (e.g., US 6,453,080 and US 6,556,721), which cite 5,880,858, but those are different patent numbers and outside the scope you requested.

Uncertainty flags

1. Filing/issue dates: authoritative full text says 1997-12-31 / 1999-03-09; Unified Patents shows 1997-12-30 / 1999-03-08. I report both rather than reconciling.
2. Examiner roles: uspto.report and Unified list "Rogers, Scott" and "Grant, II, Jerome"; sources differ on which is primary vs. assistant.
3. No CAFC 2026 docket was found — this is a negative finding, not a confirmation that none exists. If you need certainty, this should be verified directly against PACER/CM-ECF and the Federal Circuit's docket system rather than inferred from general web search.

I'll research litigation involving US patent 5880858. Let me search several sources.

Let me search litigation databases and the Unified Patents portal.

Summary Answer

I found no litigation involving U.S. Patent No. 5,880,858 in any of the sources I could reach. Based on my searches, there is no publicly reported district court case, Federal Circuit appeal, or PTAB proceeding that asserts or adjudicates this specific patent.

I want to be explicit about the limits of that negative finding, and about one case that is easy to confuse with this patent but is not about it.

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1. What I searched (and what it returned)

The aggressive search terms I ran (e.g., "5,880,858" OR "5880858" patent infringement complaint, Transpacific Optics LLC patent litigation 5880858) returned no case dockets, complaints, or opinions tied to this patent number.

2. The near-miss you should NOT treat as litigation on this patent

One result concerned Hewlett-Packard Company v. Mustek Systems, Inc. and Mustek, Inc., Nos. 02-1372, -1395, -1465 (Fed. Cir. 2003). Because Mustek was the original assignee of the patent at issue here, this case can look superficially relevant. It is not:

• That case involved HP's patents — U.S. Patent No. 5,336,878 and the '635 patent — not the '858 patent.
• Mustek was the defendant/accused infringer there; the '858 patent appears in the record, if at all, only as prior-art/background technology (the opinion discusses a "Mustek scanner" as prior art against HP's claims).
• Auto-cropping was not the subject matter.

So this is a different patent, different parties in interest, and different technology. Do not cite it as litigation involving US 5,880,858.

3. Patent identification (interpreted literally, per your instruction)

• Patent: US 5,880,858 A — "Method of auto-cropping images for scanners"
• Application: US 09/001,979; filed 1997-12-31; granted 1999-03-09
• Inventor: Yuan-Chang Jin
• Original assignee: Mustek Systems Inc. (assignment recorded 1997-12-31, effective 1997-12-18)
• Chain of title: → Transpacific Optics LLC (recorded 2006-01-17, effective 2005-12-02) → Intellectual Ventures Assets 161 LLC (recorded 2020-02-19, effective 2019-11-26)
• Legal status: Expired – Lifetime; anticipated expiration 2017-12-31

Note: the Unified Patents page lists the expiration date as 2017-12-30 while Google Patents lists 2017-12-31. I'm reporting both as found rather than harmonizing them. Either way, the patent term has run, which materially limits the universe of possible infringement suits (any would have had to be filed by late 2017).

4. Important caveats (why "none found" ≠ "none exists")

My access here is general web search, not a direct query into the authoritative litigation dockets. The following could contain cases that did not surface:

• PACER / CourtListener RECAP — full docket-level coverage requires direct docket queries.
• Docket Navigator, Lex Machina, RPX Insight, Unified Patents litigation caselist — these are the standard tools for NPE assertion histories; the Unified patent page returned no litigation entries, but I could not complete a direct query of the litigation caselist endpoint before hitting tool limits.
• Transpacific Optics LLC / Transpacific Systems LLC / Transpacific IP assertion campaigns — this family of Acacia-affiliated entities filed many scanner- and imaging-related suits around 2005–2015. It is plausible (but not confirmed) that this patent appeared in a complaint or a licensing/portfolio demand letter that never produced a reported opinion. I cannot state that any such case exists.

5. Bottom line

• Known litigation involving US 5,880,858: none identified.
• No plaintiff, defendant, jurisdiction, case number, filing date, or outcome can be reported, because no case was located in the sources searched.
• If you need a court-admissible negative assertion, I recommend a direct query of PACER/Docket Navigator/Lex Machina for the patent number and for the assignees of record (Mustek Systems, Transpacific Optics LLC, Transpacific Systems LLC, Intellectual Ventures Assets 161 LLC), plus a review of the Unified Patents litigation caselist and RPX/IV assertion records. I did not have that level of access here, and I will not fabricate a case number or party list to fill the gap.

I'll verify the structured "no proceedings" default against public sources before reporting.

Proceedings overview

Total AIA trial proceedings on file for US 5,880,858: 0. The USPTO Open Data Portal returns no AIA trial proceedings (no IPR, no PGR, no CBM), and independent web searching surfaced no PTAB petition, institution decision, Final Written Decision, or appeal involving this patent — so the bottom line for a defendant is not "the patent survived IPRs and is hardened" but something considerably better: the '858 patent is an untested, never-challenged, long-expired patent (priority 1997-12-31; anticipated expiration 2017-12-31), and any demand letter citing it today is asserting a dead property.

Because there are no proceedings to itemize, I have not fabricated proceeding numbers, panels, or claim-level outcomes. Below is the verified negative-result record, followed by the strategic picture.

Verification record (no proceedings found)

• Structured source (canonical): "PTAB proceedings on file" block — USPTO ODP returns no AIA trial proceedings as of the most recent ingest.
• Search verification: Queries for "5,880,858" / "5880858" combined with IPR, PGR, CBM, PTAB, petition, and institution terms returned no PTAB docket entries for this patent. The only patent-specific third-party record is a portfolio database entry at Unified Patents (portal.unifiedpatents.com/patents/patent/US-5880858-A) — that is a patent-profile page, not a Unified Patents-filed challenge, and Unified Patents is not in the chain of title here.
• Google Patents prosecution/assignment record (patents.google.com/patent/US5880858/en) lists no trial-proceeding tab entries: cited art is a single reference (US 5,270,688, Apple, cited by examiner); assignee chain is Mustek Systems Inc. → Transpacific Optics LLC (2006-01-17) → Intellectual Ventures Assets 161 LLC (2020-02-19).
• No CAFC appeal of any PTAB FWD exists for this patent. The only Federal Circuit decision touching Mustek in this technology space is Hewlett-Packard Co. v. Mustek Sys., Inc., Nos. 02-1372/-1395/-1465 (Fed. Cir. Aug. 7, 2003) — which concerned U.S. 5,336,878 and U.S. 4,837,635, not the '858 patent (see the opinion at CourtListener and the Federal Circuit's summary). Do not conflate it with the '858 patent.

Why there are no proceedings (the structural reason)

Two independent gates explain the empty docket, and both matter to a defendant:

1. The patent expired. Anticipated expiration was 2017-12-31. IPRs may technically be filed against expired patents, but the remedy is limited to past damages, and the Board's practice in expired-patent cases (§ 286 lookback) makes the exercise economically pointless. No rational petitioner spends $300k–$500k to invalidate a patent whose damages tail has already run out.
2. The challenge vehicles are unavailable. The patent is pre-AIA (filed 1997-12-31), so PGR is categorically unavailable (PGR requires an effective filing date on or after 2013-03-16). CBM was theoretically available for pre-AIA patents, but it requires a claim for a "financial product or service" — this patent claims a scanner image-processing method (auto-cropping prescanned images, threshold-based row/column division, film-frame detection), which is not a covered financial product or service. IPR was the only viable AIA route, and it was never taken.

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Strategic summary

Claim status: all of claims 1–9 are UNTESTED in any PTAB forum. There are no canceled claims, no sustained claims, and no FWD anywhere — nothing has been narrowed, and nothing has been validated. Two independent claims exist: claim 1 (base auto-cropping: image-division thresholds → row division → column division → iterative re-division) and claim 5 (film-scanning variant with frame detection and a high-threshold "is a film present" check), plus dependents 2–4 and 6–9. Claims 2 and 7 claim the iterative k-means-style image-division method; claims 3–4 claim cover-closed background subtraction and the masked-region "recovery region" expansion; claims 8–9 claim reversal operations for negative film. Every one of these is legally alive-on-paper but economically void now that the term has run.

Estoppel landscape: § 315(e)(2) estoppel is a non-issue here. Because no IPR was ever instituted, no petitioner has been estopped and no prior-art ground has been burned. There is no § 315(e)(2) bar, no § 325(e)(2) bar, and no Sotera stipulation of record. There is also no § 315(b) one-year-clock problem and no Fintiv discretionary-denial question to litigate. If — hypothetically — someone wanted to challenge validity, the entire universe of § 102/§ 103 art remains available and unburdened, including system art that an IPR could never have reached (e.g., the Mustek scanner products themselves, which the 2003 HP litigation showed were used as § 102/§ 103 prior art to invalidate a different HP patent on preview-scan technology). That is a meaningful pointer: the HP v. Mustek record establishes that Mustek scanner user interfaces and preview/final-scan workflows were being used as prior art devices in the late-1990s window, which is the same conceptual space as the '858 claims.

Pattern signals: none, because there is no pattern. No petitioner filed multiple IPRs (no petitioner filed even one). The patent owner — now Intellectual Ventures Assets 161 LLC, an IV monetization vehicle, having taken assignment from Transpacific Optics LLC in 2020 — has never pursued a PTAB appeal on this patent (there being nothing to appeal). There is no defensive aggregator in the chain: Unified Patents merely indexes the patent in its portal; it does not appear as a petitioner, real party in interest, or assignee. The 2020-02-19 assignment to IV Assets 161 occurred roughly two years after expiration — consistent with a portfolio-shelving transaction rather than an active assertion campaign.

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Recommended next steps

1. Lead with expiration, not invalidity. Under 35 U.S.C. § 286, damages are recoverable only for infringement occurring within six years before the complaint is filed. The '858 patent's term ended 2017-12-31. A complaint filed today (2026) would have a § 286 window opening no earlier than 2020 — entirely after the patent expired, meaning zero recoverable damages on any theory. Ask the sender to identify (a) the asserted claims, (b) the accused products, and (c) the specific pre-2018-01-01 acts they contend infringe.

2. Demand the claim chart and the priority showing. Claims 1 and 5 are broad method claims reciting an "image-division method" and a "dot-intension number" compared to a "limit." There is no PTAB claim construction to lean on — the only construction record for the family is the § 112 ¶ 6 analysis in HP v. Mustek (which construed a different patent, the '878). A defendant has a clean slate to argue indefiniteness of "limit," "dot-intension number," and "specific range," none of which has ever been construed.

3. Preserve invalidity — it is completely unencumbered. No IPR estoppel, no prior adjudication, no § 325(d) "same art previously considered" issue beyond the single examiner-cited reference (US 5,270,688). This is a rare posture: the full § 102/§ 103 toolbox, including system/device prior art, is intact.

4. Do not rely on the absence of PTAB activity as evidence of strength. It is the opposite. Well-asserted, live patents attract IPRs; this one attracted none because its term expired and its damages value went to zero. The absence of any challenge is a signal of commercial irrelevance, not of invulnerability.

5. On monitor-and-flag. The structured ODP feed currently reports no proceedings. If you are tracking this patent for a client, set a watch on USPTO PTAB E2E / PatentCenter for US 5,880,858; but note that as a pre-AIA, expired patent in a non-financial art, the realistically available AIA vehicle (IPR) is now barred in practice by mootness and by the § 286 damages horizon.

Caveat on sourcing: I could not find, and therefore have not reported, any PTAB proceeding number, institution date, panel composition, FWD disposition, settlement, or appeal for US 5,880,858. If a proceeding exists that postdates the ODP ingest and is not yet web-indexed, it would need to be confirmed directly in PTAB E2E before reliance. I have deliberately not inferred or synthesized proceeding numbers.

I'll reconstruct the chain from the authoritative patent text and then try to enrich it with assignment-center records and NPE-list cross-references.

Good — I have the raw chain. Let me try to pull the recorded correspondents and NPE-list cross-references.

Ownership Reconstruction — US 5,880,858 A

Patent: Method of auto-cropping images for scanners
App. 09/001,979 · filed 1997‑12‑31 · granted 1999‑03‑09 · expired 2017‑12‑31 (20‑yr term)
Current assignee of record: Intellectual Ventures Assets 161 LLC (per Google Patents legal events; Unified Patents lists it as "Parent Company")

Verification note: The chain below is built from the record-bearing portions of the patent document (Google Patents legal events, which reproduce reel/frame and effective dates) cross-checked against the Unified Patents patent page. The USPTO Assignment Center correspondent-of-record field for these reels was not retrievable within this session — see the caveat under "Repeat correspondent." I have not invented any reel/frame or attorney name.

Inventors

Pattern assessment — no unusual signals. Single inventor, assignment executed pre-filing, and the assignment ran to the same entity that is the named original assignee. This is the textbook "hired-to-invent" record. There is no evidence of inventor departure within 12 months of filing, and no fire-sale of inventor-held rights.

One loose end I could not resolve: the Unified Patents portal entry for US‑5880858 also surfaces the names "Grant, II, Jerome" and "Rogers, Scott" alongside the inventor field. I could not confirm whether these are prosecution/recordal attorneys or another data field. Given they are not named on the face of the patent, I am not treating them as inventors or as correspondents of record — flagging only as unresolved.

Original assignee

Mustek Systems Inc. — Taiwanese scanner/peripheral manufacturer (Mustek Group). Shipped a product embodying the claims: yes, plausibly. The patent's entire background and all three embodiments are directed at flatbed/page-scanner pre-scan and preview-window auto-cropping (see claims 1–4, directed to "a method of auto-cropping images for scanners"). This is scanner driver / TWAIN-layer functionality of exactly the class Mustek shipped in its mid-1990s flatbed line. Primary line of business: scanner and imaging hardware manufacturing.

Current status: operating but no longer holding this IP. Mustek divested the patent (and, as shown below, a whole portfolio of Mustek patents) to Transpacific Optics LLC effective 2005‑12‑02 — consistent with an IP-monetization program rather than a corporate wind-up. I could not confirm Mustek's present corporate form within this session and will not assert dissolution or bankruptcy without a record.

Assignment timeline

Three recorded assignments exist. All three are on the register.

• 1997‑12‑18 (executed) / recorded 1997‑12‑31 — Reel 008930/0095

  • Conveyance: Assignment (assignment of inventors' interest)
  • Assignor: Jin, Yuan‑Chang
  • Assignee: Mustek Systems Inc. (Taiwan)
  • Correspondent: not retrieved — the Assignment Center correspondent field for this reel was not accessible in this session.
  • Context: original inventor-to-company assignment; no third party involved, no monetization signal.

• 2005‑12‑02 (executed) / recorded 2006‑01‑17 — Reel 017480/0325

  • Conveyance: Assignment (assignment of assignors' interest)
  • Assignor: Mustek Systems, Inc.
  • Assignee: Transpacific Optics LLC (Delaware)
  • Correspondent: not retrieved. However: an independent USPTO filing — a Statement Under 37 CFR 3.73(b) for a different Mustek patent (App. 09/828,856, "Network server for providing scanning functionality to a computer") — recites the inventor→Mustek step at reel 011695/0513 and then the Mustek→Transpacific Optics LLC step at the identical reel 017480/0325 (source PDF). That is concrete evidence that 017480/0325 is a portfolio-wide recording instrument covering many Mustek patents, not a patent-specific deed. It also confirms Transpacific Optics LLC was the standing successor-in-interest to the Mustek scanner portfolio.
  • Context: sale-to-licensing-vehicle / portfolio divestiture. Mustek, an operating scanner maker, conveyed the patent into a Delaware LLC with no product line.

• 2019‑11‑26 (executed) / recorded 2020‑02‑19 — Reel 051974/0018

  • Conveyance: Assignment (assignment of assignors' interest)
  • Assignor: Transpacific Optics LLC (Delaware)
  • Assignee: Intellectual Ventures Assets 161 LLC (Delaware)
  • Correspondent: not retrieved.
  • Context: transfer into the Intellectual Ventures aggregation estate. Critically, this transfer post‑dates the patent's 2017‑12‑31 expiration by nearly two years — it is a bulk asset conveyance, not a transfer arranged to enable assertion of this patent.

Timeline diagram

timeline
    title Ownership of US 5880858
    1997 : Filed by Mustek Systems Inc
         : Inventor assignment reel 008930/0095
    1999 : Patent issued
    2005 : Mustek assigns to Transpacific Optics LLC
         : Reel 017480/0325
    2017 : Patent term expires
    2019 : Transpacific Optics assigns to IV Assets 161
         : Reel 051974/0018

NPE / troll-pattern signals

1. Shell-entity transfer — PRESENT.
The patent left an operating scanner manufacturer and entered two successive special-purpose Delaware LLCs. Reel 017480/0325 (executed 2005‑12‑02) moved it from Mustek Systems Inc. to Transpacific Optics LLC; reel 051974/0018 (executed 2019‑11‑26) moved it to Intellectual Ventures Assets 161 LLC. Both assignees are Delaware LLCs, neither is a product manufacturer, and 017480/0325 is documented as a bulk portfolio instrument rather than a deed tied to this patent. "Assets 161" is a single-purpose holding entity by construction.

2. Known asserter in the chain — PRESENT.
The terminal assignee is an Intellectual Ventures entity — IV is named on the enumerated NPE list provided. Corroborated externally: the Unified Patents portal page for this patent lists "Parent Company: Intellectual Ventures Assets 161 LLC" (portal page). Transpacific Optics LLC is likewise the acquiring arm of the Transpacific IP licensing operation, a known patent-acquisition-and-resale business — evidenced by a separate recorded chain from a PTAB filing in which Transpacific IP Group Limited sold patents onward to Acacia Research Group LLC (reels 044625/0315 → 051192/0596), with correspondent Daniel W. Juffernbruch, Patents and Licensing LLC (PTAB record PDF). I stress that Acacia link is a different patent and is cited only to establish Transpacific's resale-to-NPE business model, not as part of this chain.

3. Repeat correspondent across the chain — UNCLEAR (data not retrieved).
This is the single most valuable missing data point. The Assignment Center correspondent-of-record for reels 008930/0095, 017480/0325 and 051974/0018 was not retrievable in this session, so I cannot test for a single repeat attorney running all three links. What I can say: reel 017480/0325 demonstrably carries multiple Mustek patents as one instrument, which is consistent with a single firm running a portfolio recording — but consistency is not proof, and I am not naming any attorney on that basis. Verify directly at the USPTO Assignment Center by searching patent 5,880,858; the reel/frame numbers above will return the correspondent fields.

4. Cascading transfers (<24 months through chained LLCs) — NOT PRESENT.
The two inter-entity transfers are 14 years apart (2005‑12‑02 → 2019‑11‑26). There is no rapid chained-LLC cascade on this patent.

5. Pre-litigation transfer — NOT PRESENT.
No infringement suit naming US‑5880858 surfaced in the sources consulted, and the 2019‑11‑26 transfer into IV Assets 161 is almost two years after the 2017‑12‑31 expiry, so it cannot have been timed to precede assertion of this patent. If an earlier campaign existed during the Valid years (1999–2017), it predates the IV link.

6. Bankruptcy fire-sale — NOT PRESENT / UNCLEAR.
No Chapter 7/11 record was surfaced for Mustek Systems Inc. or Transpacific Optics LLC. The 2005 divestiture is consistent with an IP-monetization program, not an evidenced insolvency sale. Not a finding.

7. Privateering — UNCLEAR.
The 2005 Mustek → Transpacific Optics LLC transfer has the shape of a sale into a licensing vehicle, but privateering requires evidence the NPE asserted on the operating company's behalf against its competitors. No such evidence surfaced (no SEC disclosure, no Patently‑O/EFF coverage located). Not asserted.

8. Defensive aggregator (anti-NPE) — NOT PRESENT.
The chain terminates at Intellectual Ventures Assets 161 LLC — an assertion-oriented aggregation vehicle. It does not terminate at RPX, AST, LOT Network, Unified Patents, or OIN. No neutralizing transfer occurred.

Verdict

NPE — high confidence.

Two strong signals are independently documented: (a) shell-entity transfer — the patent was conveyed out of operating scanner maker Mustek Systems Inc. into Delaware special-purpose LLCs at reel 017480/0325 (executed 2005‑12‑02) and again at reel 051974/0018 (executed 2019‑11‑26), with 017480/0325 independently shown to be a bulk Mustek-portfolio instrument; and (b) known asserter in the chain — the terminal assignee, Intellectual Ventures Assets 161 LLC, is an Intellectual Ventures entity, with the Unified Patents portal confirming the parent-company relationship.

Essential qualification: this patent expired 2017‑12‑31, and its IV acquisition (executed 2019‑11‑26) came ~23 months after expiry. So the finding is that US‑5880858 sits inside an NPE ownership estate — it is not, and cannot now be, a vehicle for a live assertion campaign. The cascading-transfer and pre-litigation-transfer signals are affirmatively absent. The correspondent-of-record field, the strongest available NPE tell, remains unverified and should be pulled before this is treated as final.

Verify: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (search patent 5,880,858) · legacy interface: https://assignment.uspto.gov/patent/index.html

I'll verify the USPTO record and the cited prior art for US 5,880,858.

Let me verify the complete cited-references list on the patent's face and check for any additional prior-art references.

Prior-Art Analysis — US 5,880,858 (US5880858A)

Search performed: USPTO-derived full-text record via Google Patents (which mirrors the USPTO grant text), uspto.report (USPTO grant data), and the Unified Patents portal. I searched only for the literal identifier 5880858 / US5880858A; results for similar numbers (e.g., US 5,880,697, US 5,888,858, US 5,880,858 vs. US 5,880, 858 variants) were excluded.

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1. Identification of the patent (confirmed)

Note on the negative/conflicting record: the Unified Patents portal lists priority 1997-12-30 / grant 1999-03-08 and expiration 2017-12-30, whereas the USPTO-derived text gives 1997-12-31 / 1999-03-09. This is a one-day offset already flagged in the earlier summary; I do not auto-correct either value. For § 102 purposes the one-day difference is immaterial (no candidate reference falls within one day of the critical date).

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2. The complete prior-art citation record for 5,880,858

This is the key finding and it is narrow: the '858 patent cites exactly one prior-art reference. The "Patent Citations (1)" table on the face of the patent (and the duplicate "Citations (1)" listing) both resolve to the same document — US 5,270,688 A. There are no U.S. patent-application-publication citations and no non-patent-literature (NPL) citations in the cited-references record.

Single-reference caveat: Because only one reference was cited, there is no "each reference anticipates claims X, Y, Z" matrix to build. I state below what the cited reference actually discloses and why, element-by-element, it does not anticipate any claim — this is a negative finding, not an unexamined one.

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3. Reference-by-reference analysis

3.1 US 5,270,688 A — Apple Computer, Inc. (the sole cited reference)

Full citation: US 5,270,688 A, "Apparatus for generating a cursor or other overlay which contrasts with the background on a computer output display," filed 1990-12-12, issued 1993-12-14, assignee Apple Computer, Inc.
Sources: https://patents.google.com/patent/US5270688 • https://uspto.report/patent/grant/[5270688](/patent/5270688) •

Brief description (grounded in the text): The '688 patent is directed to bitmapped-display cursor/overlay rendering. Its independent claim 1 recites a circuit comprising:

"means for selecting a threshold value corresponding to an approximate midpoint of a range of colors; means for determining a background value corresponding to the background pixel color; means for setting the pixel value of the moveable overlay to a minimum value if the background value is greater than the threshold value… and means for setting the pixel value of the moveable overlay to a maximum value if the background value is less than the threshold value…"

The specification explains the rationale: a cursor rendered in a contrasting color must remain discernible on both black and white backgrounds; a fixed midpoint threshold on the background pixel's color value is used to decide whether to drive the overlay pixel to maximum (white) or minimum (black). Dependent claims 2–20 add antialiasing / blending of overlay and background pixel values via multiplexors.

Which claim(s) of 5,880,858 does '688 potentially anticipate under § 102?

Answer: none. Under § 102 a single reference must disclose every element of a given claim as arranged. '688 lacks the essential elements of both independent claims:

Evaluation under § 102: The only conceptual overlap is step (a)/(b) of claim 1 and the threshold-comparison of claim 2 — i.e., "comparing a pixel's color value against a threshold." That is precisely the general technique '858 itself characterizes as old:

"In general, a fixed threshold is adopted in the conventional image-division method. The image data are compared with the fixed threshold to divide the image data into two groups." (US 5,880,858, Description)

The '688 threshold is a single, fixed, pre-selected midpoint — the opposite of the claimed adaptive, iterative low/high threshold pair. There is also no cropping, no prescan, no row/column projection, and no image-division clustering anywhere in '688. No claim of 5,880,858 is anticipated by US 5,270,688 under § 102.

Most likely reason for citation: '688 was almost certainly cited as general background art (pre-AIA § 102(a) or as § 103 context) for the isolated idea of thresholding a pixel value against the background to separate foreground from background — not as an anticipating reference. This is consistent with the extrinsic-evidence weighting the examiner gave the '858 references list.

⚠️ Uncertainty flag: I was not able to retrieve the actual USPTO file wrapper (prosecution history / examiner's statement of reasons for allowance) for application 09/001,979 during this analysis. My characterization of why '688 was cited is an inference from the reference's content, not a quotation from the examiner. Verify against PatentCenter if certainty on the examiner's rationale is required.

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4. Important disambiguation: "Cited By" entries are not prior art to '858

The Google Patents record shows large "Cited By" tables (43 entries in one snapshot, 133 in another) and a "Similar Documents" table. These are forward citations — later patents citing '858 — and therefore cannot be prior art under § 102 against '858. For completeness, they include:

• Same-family Mustek/Transpacific follow-ons: US 6,453,080 B1 ("Method for real-time auto-cropping a scanned image," Mustek, filed 1999-10-11, issued 2002-09-17) and US 6,556,721 B1 ("Method for image auto-cropping," Mustek, priority 2000-01-07, issued 2003-04-29).
• US 7,912,295 B1 / US 2007/0058864 A1 / US 7,418,140 B2 ("Method for auto-cropping a scanned image," priority 1999-09-28, Transpacific Optics LLC).
• Large unrelated clusters (e.g., the Flexiworld Technologies wireless-printing family, Sony media-production family) that cite '858 only incidentally.

These are outside the requested scope (they are not citations of '858's prior art, but citations to '858) and are listed only to prevent a common error — treating a "Cited By" list as a prior-art list.

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5. Bottom line

Verification gaps I will not paper over: (i) the USPTO file wrapper for 09/001,979 was not retrieved, so the examiner's citation rationale is inferred, not quoted; (ii) the one-day filing/issue discrepancy between the USPTO-derived text (1997-12-31 / 1999-03-09) and Unified Patents (1997-12-30 / 1999-03-08) remains unresolved and is reported as-is rather than auto-corrected.

I'll research the prior art cited on the page and related pre-1997 art to ground the obviousness analysis.

Let me pull a few more targeted pre-1997 references for the specific claim elements.

Obviousness Analysis — US 5,880,858 under 35 U.S.C. § 103

Note on scope and provenance. This builds on the earlier summary (bibliographic data, claim overviews) without repeating it. The statutory framework is pre‑AIA § 103 (application filed 1997‑12‑31; no pre‑AIA § 102/103 amendments apply). The "Prior Art" section of the analyzed page cites only one examiner reference — US 5,270,688 (Dawson/Drako, Apple Computer) — and a long forward-citation list. Because a bare face-of-patent citation set is not a substitute for a prior-art search, I supplement with the contemporaneous, well-documented art located in search. Where a reference comes from that supplemental search rather than the page itself, I say so. All references are treated as prior art as of the 1997‑12‑31 effective date; anything with a § 102(e) filing date before that date qualifies.

A threshold caution: this is a technical invalidity-style analysis, not a legal opinion. The patent is expired (anticipated expiry 2017‑12‑31), so the practical stakes are historical/defensive. Reference characterizations below should be verified against the originals before being relied on in any filing.

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1. Level of ordinary skill in the art (Graham prong 1)

For the 1997 timeframe, a POSITA in this field would have had a bachelor's degree in electrical engineering or computer science plus roughly 2+ years of experience in document image analysis / scanner image processing, or equivalent. That person would have been familiar with: (i) global and locally adaptive image thresholding (Otsu, Ridler–Calvard, co-occurrence/2-D histogram methods); (ii) projection-profile page segmentation and the recursive X–Y cut; (iii) scanner shading/background calibration; and (iv) the mechanics of film carriers, slide mounts, and pre-scan/main-scan film scanners. This is a low-to-moderate skill level in a mature, well-published art — which matters under KSR.

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2. Reference set

On the page (Prior Art section):

Supplemental (contemporaneous literature/patents located in search):

• Recursive X–Y cut literature: Nagy & Seth, "Hierarchical Representation of Optically Scanned Documents," 7th ICPR (1984), 347–349; Nagy, Seth & Stoddard, "Document Analysis with an Expert System," Pattern Recognition in Practice II (1984), 149–155; Nagy, Seth & Viswanathan, IEEE Computer 25(7):10–22 (July 1992); "Recursive X–Y Cut Using Bounding Boxes of Connected Components," Proc. ICDAR 1995 (DOI 10.1109/ICDAR.1995.602059); Haralick & Shapiro, Computer and Robot Vision, Vol. I, Addison‑Wesley (1992).
• Adaptive thresholding: Ridler & Calvard, "Picture Thresholding Using an Iterative Selection Method," IEEE Trans. SMC‑8:630 (1978); Otsu, IEEE Trans. SMC‑9(2):62–66 (1979); "A Hardware Structure for the Automatic Selection of Multi‑level Thresholds in Digital Images," Pattern Recognition (1992), DOI 10.1016/0031‑3203(92)90124‑2 (explicitly extends the Ridler–Calvard iterative scheme to multi-level/multi-class thresholding).
• US 5,651,077 — Hewlett‑Packard, "Automatic Threshold Determination for a Digital Scanner," filed 1993‑12‑21, issued 1997‑07‑22 (listed under "Similar Documents" on the page; pre‑date art). Computes per-cell "influence," "weight," and "center of mass" to derive a scanner threshold.
• US 5,371,614 — film image reader (slide carrier, shading correction). Notably computes a pixel-element count from a known physical dimension: number of picture elements = W × B / d (window width × imaging magnification ÷ element pitch). Directly relevant to claim 6's physical-size-to-pixel conversion.
• US 5,461,492 — Kodak film scanner with dual negative/slide gates, low-resolution pre-scan then high-resolution main scan, slide-mount centering.
• US 5,555,042 — Kodak, slide feeding/centering "regardless of variations in slide mount length, width and thickness."
• EP 0 804 013 B1 / EP 0 804 020 A3 — film scanners that recognize carrier/film type and set pre-scan parameters accordingly.
• US 6,100,960 (Sato et al., Canon) — film scanner that sets a per-frame read area from recorded frame information; filed 1997‑07‑14, JP priority 1996‑07‑16 (qualifies as § 102(e)/foreign-priority art). Confirms the "preview then crop the read area" workflow and frame-based read-area control.

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3. Claim construction of the load-bearing terms

• "dot-intension number" (claim 1(b)/(c), claim 5) — the count of pixels in a row/column whose value exceeds the low threshold. Functionally this is a projection profile (row/column histogram of foreground pixels).
• "limit" — the count threshold above which a row/column "contains content"; functionally the minimum-profile-value / valley criterion used in X–Y cut.
• "image-division method … low threshold and high threshold" — adaptive (data-derived) clustering of pixel values into at least two classes, yielding the min-class mean (low) and max-class mean (high). This is the point of novelty over a fixed threshold, which the specification itself concedes was conventional.
• "cropped"/"dividing" — computing a bounding sub-region, not a physical paper cut.

Under these constructions, the claim maps almost one-to-one onto recursive X–Y cut performed on an adaptively binarized image.

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4. Claim-by-claim § 103 analysis

Claim 1 — core auto-crop (strongest obviousness case)

Proposed combination: Nagy/Seth/Nagy–Viswanathan X–Y cut (primary) + Ridler–Calvard/Otsu adaptive thresholding (secondary) + US 5,270,688 (threshold-comparison teachings).

Motivation to combine (KSR factors):

1. Same field, same problem. Both X–Y cut and the '858 invention solve "locate discrete objects on a page/platen." X–Y cut was developed expressly for optically scanned documents — the identical input medium.
2. Self-evident motivation in the background. The '858 specification admits conventional scanners required manual cropping and that fixed-threshold division was the norm. The POSITA seeking automation had only to reach for the field's standard segmentation tool (X–Y cut) and the field's standard fix for its known weakness (non-uniform/inadequate fixed thresholds → adaptive thresholding).
3. Predictable results / finite solutions. Replacing a fixed threshold with an adaptive one in a projection-profile segmenter does not change the segmenter's operation; it only changes the binarization input. KSR ("a finite number of identified, predictable solutions").
4. US 5,270,688 in the combination supplies the claim's threshold-comparison framing and even the "approximate midpoint of the range of colors" heuristic — i.e., an explicit teaching to derive the comparison level from the data rather than fix it. Even though it is about cursor overlays, it is analogous art on the pixel-threshold-comparison subroutine, and one of ordinary skill would consult it for that subroutine.

Counterargument the applicant would raise: X–Y cut traditionally cuts at near-zero projection valleys, whereas '858 counts pixels above a threshold and compares to a limit. Answer: the distinction is one of degree, not of kind — a valley of a binary projection profile is precisely "few pixels exceed the foreground threshold." No claim language excludes valley-based implementations.

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Claim 2 (and its twin, claim 7) — the iterative clustering "image-division method"

Combination: Ridler–Calvard (1978) / Otsu (1979) iterative selection + multi-level extension (Pattern Recognition, 1992), optionally with a pattern-recognition textbook (Duda & Hart / Haralick & Shapiro) as evidence of the ordinary skill level.

Claim 2's algorithm is: pick initial centroids a₁ < … < aₙ; assign each pixel to the nearest centroid by absolute difference; recompute set means; iterate until |Tᵢ − aᵢ| ≤ tolerance; take min/max means as the low/high thresholds. This is the textbook k-means / "isodata" clustering algorithm, and for the n=2 case it is literally Ridler–Calvard iterative-selection thresholding (which iterates the class means until the threshold stabilizes). The 1992 Pattern Recognition paper extends Ridler–Calvard to multi-level thresholding, supplying claim 2's plurality of sets S₁…Sₙ and the example seeds (a₁=3, a₂=250 map to the darkest/brightest class centers). The tolerance test |Tᵢ−aᵢ| is the standard convergence criterion of the iterative-selection method (see the Ridler–Calvard descriptions: iteration stops when |T_{i+1}−T_i| is sufficiently small).

Motivation: (i) Ridler–Calvard and Otsu were the default scanner/document binarization methods by the mid‑1990s; (ii) the specification itself motivates multi-level division ("If the image intension requires being divided more finely, more initial values can be added"), which is exactly a design choice KSR treats as obvious when the improvement is a mere extension of a known technique to a known number of levels. Claim 2 is the weakest link in the patent.

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Claim 3 — background pre-scan, cover-open/closed detection, subtraction

Combination: scanner background/shading-calibration art + the claim-1 combination.

The claim adds: pre-scan and store a background image; detect cover state; if closed, subtract the stored background from the pre-scan before cropping. Background/dark-current and shading calibration by pre-scanning the illumination field is old and standard in scanners — US 5,371,614 expressly performs shading correction continuously "just before the start of reading," and Kodak-class film/drum scanners all used background/white-reference capture. Subtraction of a stored background frame is the canonical flat-field/defect-removal step, and the specification's stated purpose (cancel the cover's non-black background color and stray "connection lines") is a predictable benefit of a known technique (KSR).

Uncertainty flag: the page's search did not surface a single pre‑1997 reference that squarely claims cover open/closed detection for the purpose of selectively enabling the subtraction. I would not assert anticipation of claim 3 on the current record; the obviousness theory rests on the ubiquity of background subtraction plus routine sensor/switch design. A full search may find closer art (e.g., platen-cover sensors are pervasive in copier art). This should be verified.

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Claim 4 — mask a margin strip, crop unmasked region, then "expand" into the mask as a recovery region

Combination: the claim-3 combination + zone-masking/region-growing art.

The claim's masking-and-recovery step (mask a strip wider than the interfering line, crop the visible portions, then grow the crop back across the mask and re-run the crop to recover objects hidden under the mask) finds structural analogues in US 5,555,042 (centering slides "regardless of variations in slide mount length, width and thickness" — i.e., tolerating masking at mount edges) and in the patent's own third-embodiment margin masking. Region-growing/bounding-box expansion into a masked band is a routine extension.

This claim is the hardest of claims 1–4 to invalidate. The specific order — crop the unmasked part first, then deliberately expand the recovered bounding box back across the masked band and re-crop — is a more particular combination than claims 1–3, and I did not locate art that performs that exact ordered recovery. It is vulnerable to a "teaching away is absent, but the specific two-pass recovery is not shown" argument. I flag it as the claim most likely to survive a § 103 challenge on this record, with the caveat that a targeted search (document-analysis masking, strip-mask recovery) could change that.

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Claim 5 — film auto-crop: frame detection filter + iterative crop + occupancy check

Combination: claim-1 combination + film-scanner art (US 5,461,492; US 6,100,960; EP 0 804 013) + a routine threshold "empty-slot" test.

Claim 5's two additions over claim 1 are (i) gating on frame detection, and (ii) an occupancy check: for each cropped region, count pixels exceeding the high threshold; if the count exceeds a set proportion of the region's pixels, declare the slot empty.

• Pre-scan→locate→crop for film is shown by US 6,100,960 (Canon) and US 5,461,492 (Kodak): both do a low-resolution preview and then set the read/trim area per frame. US 6,100,960 even touts that "trimming works can be omitted."
• The occupancy test is an application of the same high threshold already derived in claim 1(a). Testing whether a region is "mostly background" by counting background-class pixels is the standard blank-page / blank-region discriminator (see the "Similar Documents" listing EP 0 768 000 B1, "Automatic Determination of Blank Pages and Bounding Boxes for Binary Images") combined with any adaptive-threshold classifier.
• Motivation: film holders have fixed, known slot positions, some occupied and some empty; discarding empties is the obvious efficiency step once you have a high/low classifier in hand. KSR "known technique to improve similar device in the same way."

The frame-detection filter element overlaps claim 6 (below).

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Claim 6 — frame detection using known holder size converted to pixel dots

Combination: claim-5 combination + US 5,371,614's physical-size-to-pixel conversion + film-holder dimension art (US 5,555,042).

Claim 6 computes pc = (3.6/2.54) × prescan_dpi and declares a frame present when ≥2 recorded row numbers fall within ±sn of pc. US 5,371,614 teaches exactly the enabling step — converting a known physical width into a picture-element count (W × B / d). Given the 35 mm slide aperture (~3.6 cm, a standardized value) and the scanner's known pre-scan dpi, the arithmetic is a straightforward unit conversion; the ±sn tolerance band is a routine engineering margin. US 5,555,042 confirms that slide-mount dimensions were known quantities that scanners were expected to accommodate. Motivation: recognizing "is a frame present, and where are its slots?" from the known, invariant geometry of standardized film holders is the most natural detection route and avoids extra sensors. Claim 6 is obvious on this combination.

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Claims 8 & 9 — reversal (complement) for negatives before detection/cropping

Combination: any film-scanning reference (US 6,100,960; US 5,461,492; EP 0 804 013) + the claim-1/claim-5 combinations.

Negative film record inverted density relative to positive film; its clear areas (frame borders/background) appear black and its dense areas appear white. Complementing a negative-derived image is the definitional first step in negative processing and was universally known to anyone scanning negatives. That the same auto-cropping algorithm then applies symmetrically to positives (no reversal) and negatives (reversal) is a predictable, mechanical choice under KSR. Claims 8–9 add no patentable weight beyond the film-type handling already inherent in film-scanner art.

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5. Summary claim chart

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6. Graham / secondary considerations

• Scope and content of prior art: mature, densely published art (X–Y cut, thresholding, scanner calibration, film carriers) — all pre‑1997.
• Differences: the only genuine departures from the art are (i) combining adaptive thresholds with X–Y cut, and (ii) the claim-4 ordered mask-recovery pass. The former is a predictable substitution; the latter is the sole element with arguable non-obviousness.
• No objective indicia offered: the record on the page shows no unexpected results, no long-felt-need evidence tied to the claims, and no nexus evidence. The patent's own specification frames the benefit as "convenience and efficiency" — i.e., the expected result of automating a manual step, not a surprising one. An expired patent with this posture carries no KSR presumption of validity for this analysis.
• Why the examiner missed it: the face of the patent shows only US 5,270,688 cited — a display-cursor reference, not the document-image-analysis literature where the real teaching (X–Y cut) lives. That the examiner's art was from a different sub-field (graphics cursors) explains issuance without undermining the § 103 case; the operative teachings were in a different art community's journals (ICDAR, IEEE Computer, Pattern Recognition) and textbooks (Haralick & Shapiro) that the record suggests were never applied.

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7. Bottom line and uncertainty flags

Strongest invalidity theory (claims 1, 2, 5–9): Nagy/Seth recursive X–Y cut (projection profiles, alternating horizontal/vertical cuts, iterate to convergence) in view of Ridler–Calvard/Otsu iterative adaptive thresholding (and its multi-level extension), further in view of scanner-specific art (US 5,651,077; US 5,371,614; US 6,100,960; US 5,461,492) for the scanner/film context. Motivation is supplied by the identical field and problem, the admitted conventionality of fixed thresholds, and KSR's finite-solutions / predictable-results / known-technique rationales.

Weaker points requiring verification before reliance:

1. Claim 4 — I did not locate art teaching the exact "crop-unmasked-then-expand-into-mask-and-recrop" order; treat its invalidity as unproven on this record.
2. Claim 3 — background subtraction is clearly known, but a specific pre‑1997 cover-open/close-gated subtraction reference was not surfaced; verify against copier/platen-sensor art.
3. All supplemental references were located via general web search and should be pulled in their original form (full text, claim language, actual publication dates) before being cited formally; the page under analysis formally cites only US 5,270,688.
4. Dates: I use the authoritative 1997‑12‑31 filing / 1999‑03‑09 grant dates from the page's full text; a one-day discrepancy noted earlier in the summary (1997‑12‑30/1999‑03‑08) is immaterial to any § 103 analysis here because it does not cross any reference's critical date except, potentially, US 6,100,960 (filed 1997‑07‑14) — which is prior art under either figure.

I have no high-confidence single reference that anticipates claim 1 outright; the case is strongest as a § 103 combination, not a § 102 anticipation. If a stricter posture is required, the priority-verification and claim-4/claim-3 gaps above are where the analysis would need reinforcement.