Invalidity dossier
US 3949072
Topical composition for treatment of seborrheic keratosis
Current assignee: Individual
Added 9/23/2026, 1:05:28 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 3,949,072 A
Title: Topical composition for treatment of seborrheic keratosis
Inventor / Assignee: Louis T. Tenta (inventor); original assignee listed as "Individual."
Key dates: Priority date 1971-03-11 (claimed from application US00123380A, which issued as US 3,821,370); filing date 1974-05-01; granted/publication date 1976-04-06; anticipated expiration 1993-04-06. Legal status listed as "Expired - Lifetime." The application is a continuation-in-part of Ser. No. 123,380, filed Mar. 11, 1971, now U.S. Pat. No. 3,821,370.
Purpose: To improve the external appearance caused by seborrheic keratosis by providing a superficial slough (peeling) of the epidermis, applied topically in non-surgical fashion without harm to health.
Plain-language scope: The claimed composition has five essential ingredients:
- An "inhibited phenol" — potassium phenate, sodium phenate, or ammonium phenate — at 5–25 parts by weight, calculated as potassium phenate (approximately 70% of which is equivalent phenol). A preferred range is 10–20 parts, most preferably about 18–19 parts.
- A salicylate (sodium salicylate or zinc salicylate) at ½–2 parts.
- Resorcinol at 1–5 parts.
- A zinc compound (e.g., zinc oxide, zinc sulfate, zinc salicylate) at 1–4 parts, calculated as zinc sulfate.
- A non-aqueous solvent system including a hydrophilic, non-toxic lower aliphatic alcohol (2–4 carbon atoms), to bring the total to 100 parts. Preferred solvent systems: ~61.5% benzyl alcohol / 38.5% ethanol, or 50% propylene glycol / 50% ethanol.
The inhibited phenol is activated by moisture from air or skin. The composition may be a solution or a gel, using hydroxyethylcellulose (preferred) or carboxymethyl cellulose at about 5–15% by weight. A solution containing 1 gram of potassium phenate reportedly treats roughly 200 cm² of skin. The specification states these formulations are more stable and clinically active at lower active-ingredient concentrations than prior systems.
Source: https://patents.google.com/patent/US3949072/en
What the excerpt does not establish: The supplied source contains no claims text (only classification, abstract, and description excerpts), no examples 1–6 formulations in full, no clinical trial data, no efficacy or safety conclusions, and no information on litigation, ownership transfers, or validity. The abstract and description describe the composition, but the excerpt does not establish the exact scope of the granted claims.
Generated 10/1/2026, 9:53:17 PM
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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