Invalidity dossier

US 8758418

Illuminator for photodynamic therapy

Current assignee: Dusa Pharmaceuticals Inc Canada

Added 8/27/2026, 8:57:31 AM

IndustryMedical (M)
At a glanceNo PTAB challengesNo litigation on fileMedical (M)

Active provider: DeepSeek · deepseek-v4-flash

Auto-generating section 1 of 7: Litigation summary

Each section takes ~30-60s with web-search grounding. Keep this tab open — sections will fill in below as they complete.

Patent summary

Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.

✓ Generated

I'll search for information on this specific patent number in the USPTO database and any CAFC litigation records.

The initial searches returned no results. Let me try additional search variations.

I have gathered sufficient authoritative information from the provided patent text and corroborating search results (PubChem, FreePatentsOnline, DrugPatentWatch, USPTO.report). Here is the requested summary.


US Patent 8,758,418 — Summary

Note on the search: I could not locate any CAFC (U.S. Court of Appeals for the Federal Circuit) docket entries for this patent in 2026 or any other year via the searches performed. Google Patents does flag the patent family as having litigation (linked to a Darts-ip family record), but I found no specific CAFC appeal docket tied to this exact patent number. Treat the absence of CAFC records as unconfirmed rather than definitive.

Bibliographic Data

Field Value
Patent number US 8,758,418 B2
Title Illuminator for photodynamic therapy
Application number US 13/484,691
Filing date May 31, 2012
Issue (grant) date June 24, 2014
Priority date May 1, 1998 (chain back to US 09/070,772 → US 6,223,071)
Inventors Scott Lundahl, Rebecca Kozodoy, Ronald Carroll, Elton Leppelmeier
Assignee Dusa Pharmaceuticals Inc. (also listed in some records as "Dusa Pharmaceuticals Inc Canada" / "Dusa Pharmaceuticals Inc")
Status Expired – Fee Related; anticipated expiration date listed as 2018-05-01
Claim count 44 claims

The patent is a continuation in a long chain: 09/070,772 (→ US 6,223,071) → 09/774,084 (→ US 6,709,446) → 10/755,318 (→ US 7,190,109) → 11/716,014 (→ US 7,723,910) → 12/621,845 → 12/969,999 → 13/484,691 (this patent). A further continuation, US 14/282,636, issued as US 9,723,991.

Abstract

An apparatus and method for photodynamic therapy or photodynamic diagnosis using an illuminator comprising a plurality of light sources generally conforming to a contoured surface and irradiating the contoured surface with substantially uniform intensity visible light. The light sources may comprise generally U-shaped fluorescent tubes that are driven by electronic ballasts. The spacing of the U-shaped tubes is varied to increase the output at the edges of the illuminator to make the output more uniform. Also, different portions of the tubes are cooled at different amounts, to improve uniformity. A light sensor monitors output from the U-shaped tubes to provide a signal for adjusting the output from the tubes.

Independent Claims — Plain-Language Overview

The patent's granted claims are all method-of-treatment claims (not apparatus claims, despite the title). There are four independent claims; the remaining 40 claims depend from them.

Claim 1 — Photodynamic treatment with a defined power range: Administer 5-aminolevulinic acid (ALA) to at least part of a patient, then irradiate the patient with substantially uniform visible light from multiple light sources at a power of 9.3 to 10.7 mW/cm².

Claim 12 — Dose-capped treatment: Administer ALA, irradiate with substantially uniform visible light from multiple light sources, and stop irradiation once a dose of 10 J/cm² has been delivered.

Claim 23 — Time-capped treatment: Administer ALA, irradiate with substantially uniform visible light from multiple light sources, and stop irradiation after 1,000 seconds of light delivery (which corresponds to the 10 J/cm² dose at 10 mW/cm² per the specification).

Claim 34 — Blue-light dose-capped treatment: Administer ALA, irradiate with substantially uniform blue light from multiple light sources, and stop when a dose of 10 J/cm² has been delivered.

Dependent Claim Themes

The dependent claims narrow the independent claims by:

  • Irradiating with fluorescent tubes;
  • Using light substantially entirely within the blue region;
  • Topically applying ALA (vs. injecting) and admixing ALA with a vehicle just prior to use;
  • Treating specific indications: actinic keratosis, acne, photo damaged skin, cancer, and pre-cancerous conditions.

Notes / Uncertainty

  • CAFC 2026 dockets: No CAFC docket records were found for patent 8,758,418 in my searches. If you need confirmation of litigation status, the Darts-ip family record linked from Google Patents (family ID 5472388) would be the next place to check, but I could not verify its contents.
  • Assignee: Google Patents lists the current assignee as "Dusa Pharmaceuticals Inc Canada" with original assignee "Dusa Pharmaceuticals Inc"; DrugPatentWatch lists "Dusa Pharmaceuticals Inc." This reflects the same corporate entity family, but I did not verify the precise current legal entity.
  • Expiration: The "anticipated expiration" of 2018-05-01 reflects the 20-years-from-priority-date calculation; the patent is marked "Expired – Fee Related," meaning it lapsed due to unpaid maintenance fees rather than reaching a natural statutory term endpoint.

Generated 8/27/2026, 8:57:52 AM

Cases on file (0)

Specific litigation cases in our database that name US patent 8758418. 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.

Not generated yet. Click Generate to call the active LLM provider with the configured prompt.

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.

Not generated yet. Click Generate to call the active LLM provider with the configured prompt.

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.

Not generated yet. Click Generate to call the active LLM provider with the configured prompt.

Prior art

Earlier patents, publications, and products that may anticipate or render the claims unpatentable.

Not generated yet. Click Generate to call the active LLM provider with the configured prompt.

Obviousness

Combinations of prior art that suggest the claimed invention would have been obvious under 35 U.S.C. § 103.

Not generated yet. Click Generate to call the active LLM provider with the configured prompt.

Extensions

Patent term adjustments, term extensions, continuations, divisionals, family members, and expiration dates.

Not generated yet. Click Generate to call the active LLM provider with the configured prompt.

Derivative works

Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.

Not generated yet. Click Generate to call the active LLM provider with the configured prompt.

Keep exploring

Other patents in Medical (M)

See all Medical (M) patents →