United States Patent 4,387,089 (US4387089): Scope, Claim Coverage, and US Sunscreen/UV Filter Patent Landscape
US Patent 4,387,089 claims a specific dibenzoylmethane UV filter structure: 4-(1,1-dimethylethyl)-4’-methoxydibenzoylmethane (as the active UV-A absorber), plus compositions and topical methods that use defined concentration windows and, in some dependent claims, a pairing with 2-ethylhexyl p-methoxycinnamate (a UV-B filter). The patent scope is anchored to (i) the molecular entity and (ii) sunscreen/light-screen formulations where the entity is present at defined wt.% levels in cosmetic carriers, including combinations with a UV-B filter.
What does US 4,387,089 claim, and what is the core protected UV filter?
Claim 1 coverage: the compound itself
Claim 1 is product-by-structure protection for the exact chemical name:
- 4-(1,1-dimethylethyl)-4’-methoxydibenzoylmethane
Practical scope
- The literal claim covers the active ingredient itself, regardless of formulation.
- If a competitor makes, sells, or uses this exact compound in the US, Claim 1 is the starting infringement hook, independent of whether it is used in a sunscreen or another cosmetic.
How do the composition claims narrow the claim scope?
US 4,387,089 then layers formulation protection around Claim 1 via dependent claims on:
- “light-screen composition” with an “effective ultra violet absorbing amount” of the compound plus at least one other organic material (Claim 2)
- a specific pairing with a UV-B filter (Claim 3)
- concentration ranges (Claims 4 and 5 and also later formulation concentration ranges in claims 12–13)
- specific inclusion in cosmetic bases and topical carriers (Claims 6, 10–12, 14–17)
How broad is Claim 2’s “light-screen composition” definition?
Claim 2: “effective ultra violet absorbing amount” + “at least one other organic material”
Claim 2 covers:
- A light-screen composition with
- an “effective ultra violet absorbing amount” of 4-(1,1-dimethylethyl)-4’-methoxydibenzoylmethane, and
- at least one other organic material.
Scope characteristics
- Broad on partners: “at least one other organic material” does not limit the other ingredient class. Excipients, emollients, film-formers, preservatives, and other UV filters can all qualify as “other organic material,” subject to further limitations in dependent claims.
- Broad on dose: “effective” is functional and can be argued across a wide range of UV performance doses, constrained mainly by Claim 4/5/12–13 which supply explicit wt.% ranges.
Claim 3: “contains UV B-filter”
Claim 3 narrows Claim 2 by adding:
- the composition includes UV B-filter.
Scope characteristics
- It does not limit the specific UV-B filter in Claim 3; it simply requires a UV-B filter category.
- Claim 5 and later dependent claims narrow the UV-B partner to 2-ethylhexyl p-methoxycinnamate.
What is the significance of the wt.% windows (Claims 4 and 5), and how do they affect infringement?
Claim 4: 1–6 wt.% of the UV-A filter (within Claim 2/3 family)
Claim 4 limits Claim 2/3 to compositions where:
- about 1 wt.% to 6 wt.% of 4-(1,1-dimethylethyl)-4’-methoxydibenzoylmethane is present.
Infringement impact
- If a competitor formulates below ~1 wt.%, they may try to avoid Claim 4’s literal concentration window, but Claim 2 can still apply due to the “effective amount” language unless a court construes “effective” as requiring a comparable dose.
- If a competitor formulates above ~6 wt.%, Claim 4 does not fit literally, but again Claim 2 may still be asserted depending on “effective” dose arguments.
Claim 5: “sun-screen composition” with specific two-filter combination
Claim 5 covers a sunscreen composition with:
- 2 wt.% to 5 wt.% of 4-(1,1-dimethylethyl)-4’-methoxydibenzoylmethane, and
- 2.0 wt.% to 10.0 wt.% of 2-ethylhexyl p-methoxycinnamate.
This is the cleanest, most litigation-ready dependent claim
- It ties the formulation to a specific UV-B filter species and fixed concentration windows for both UV-A and UV-B filters.
- A product that matches those ranges and uses the exact UV-A filter is squarely within Claim 5.
What do the method claims protect: manufacturing incorporation vs topical use?
Claim 6–9: method for preparing a light screening composition in a cosmetic base
Claim 6 covers:
- A method for preparing a light-screen composition by incorporating the UV-A filter into a cosmetic base.
Claim 7 narrows to:
- Incorporation amount 1% to 6% by weight of the total composition.
Claim 8 adds:
- the incorporation method also includes a UV B-filter.
Claim 9 narrows further to:
- includes 1% to 12% by weight of 2-ethylhexyl p-methoxycinnamate.
Key point for enforcement
- These are process claims focused on how a formulation is made and what amount of the compound and UV-B filter is included.
- If a competitor uses a different process that still results in the claimed end product, they may avoid the process claims while still risking product claims (Claim 2/3/4/5 and later topical preparation and use claims).
Claim 10–13: topical preparation for application on the skin
Claim 10 covers:
- A topical preparation for skin application comprising an effective amount of the UV-A absorber in a suitable carrier.
Claim 11 narrows the carrier to a cosmetic base.
Claim 12 narrows the UV-A level to:
Claim 13 narrows both UV-A and UV-B levels:
- UV-A: 2% to 5% by weight
- UV-B: 2-ethylhexyl p-methoxycinnamate at 2% to 10% by weight
Practical infringement positioning
- For consumer sunscreen products, Claims 10–13 are the most direct “product for topical application” hooks, especially Claim 13 due to the same two-filter concentration windows as Claim 5.
Claim 14–17: method for protecting skin from UV-A radiation
Claim 14 covers:
- A method of protecting skin from UV-A effects by applying a UV-A effective amount in a suitable carrier.
Claim 15 narrows the carrier to cosmetic base.
Claim 16 includes concentration constraint:
- UV-A present at 1% to 6% by weight.
Claim 17 adds the two-filter constraint:
- UV-A at 2% to 5% by weight
- and UV-B partner (2-ethylhexyl p-methoxycinnamate) at 2% to 10% by weight
What is the claim “sweet spot” for litigation risk?
Highest literal-fit claims
Products that use:
- 4-(1,1-dimethylethyl)-4’-methoxydibenzoylmethane
- at 2–5 wt.%
- with 2-ethylhexyl p-methoxycinnamate at 2–10 wt.%
- in a cosmetic base for topical application
are most tightly captured by:
- Claim 5 (sunscreen composition)
- Claim 13 (topical preparation)
- Claim 17 (method of protecting skin from UV-A while also including UV-B partner)
If a product deviates from concentration windows
- Below 2 wt.% UV-A filter: Claim 5/13/17 likely miss literally, but Claim 2 and Claim 10/14 still present risk because they use “effective amount.”
- Above 5 wt.% UV-A filter: same concept, Claim 5/13/17 miss literally; “effective” may still sustain other claims.
- If UV-B partner is not present: Claim 3/5/8/9/13/17 likely miss, but Claim 2 and Claim 10/14 still apply.
How does US 4,387,089 relate to typical sunscreen UV filter combinations (UV-A vs UV-B)?
This patent’s claim structure reflects a common sunscreen formulation logic:
- Use a UV-A absorbing dibenzoylmethane derivative as the core UV-A filter.
- Optionally pair with UV-B filtering cinnamate (2-ethylhexyl p-methoxycinnamate).
- Tie those combinations to commercial-ready wt.% ranges.
Implication for product design-arounds
- A meaningful risk-reduction strategy is to remove one of the required structural elements:
- the exact UV-A filter molecule in Claim 1, or
- the specific UV-B partner (2-ethylhexyl p-methoxycinnamate), or
- both concentration ranges simultaneously.
- However, because Claim 2/10/14 use functional “effective amount” language, avoiding dependent concentration windows does not guarantee freedom-to-operate.
Where does the “other organic material” language create broad coverage?
Claim 2’s “at least one other organic material”
The patent avoids limiting co-formulants. That increases coverage for:
- emulsifiers
- solvents
- film formers
- water-resistant systems
- pigments
- polymers
- any other organic additives used in a cosmetic formulation
As long as the formulation contains an “effective ultra violet absorbing amount” of the claimed UV-A filter, the “other organic material” requirement is easily met.
How many distinct infringement theories are embedded?
US 4,387,089 supports multiple theories using the same UV-A active:
- Compound-level product claim: Claim 1.
- Composition claim (product) with broad co-ingredient latitude: Claim 2.
- Composition claim with UV-B category requirement: Claim 3.
- Composition claim with defined UV-A wt.% band: Claim 4.
- Two-filter sunscreen composition with defined wt.% bands: Claim 5.
- Process claim for formulation incorporation into cosmetic base: Claims 6–9.
- Topical preparation product claims: Claims 10–13.
- Method-of-use claim for protecting skin from UV-A radiation: Claims 14–17.
This layered structure increases the chance that a competing product matches at least one asserted claim, even when it tries to steer clear of one dependent concentration window.
What is the patent estate beyond US 4,387,089, and what is the landscape risk?
No additional patent data was provided in the prompt about:
- continuation/divisional families,
- related filings in other jurisdictions,
- examiner search results,
- citing/cited patents,
- Orange Book listings (irrelevant for cosmetics unless an FDA-approved drug product),
- ANDA/Paragraph IV type litigation,
- assignees or prosecution history.
Per the constraints, this response is limited to the claim-set scope you supplied for US 4,387,089 and cannot produce a complete, accurate US competitive patent landscape (including expiration calculations, family members, or litigation status) without those inputs.
Key Takeaways
- US 4,387,089 protects 4-(1,1-dimethylethyl)-4’-methoxydibenzoylmethane as a standalone UV-A absorber (Claim 1).
- It then protects sunscreen/light-screen compositions using the UV-A absorber with broad co-ingredient tolerance (Claim 2) and optional UV-B pairing (Claim 3).
- The highest literal-risk formulation zone is the two-filter system:
- UV-A filter 2–5 wt.%
- UV-B filter 2-ethylhexyl p-methoxycinnamate 2–10 wt.%
Covered by Claims 5, 13, and 17.
- Even outside those bands, the patent still creates exposure through “effective amount” language in Claims 2, 10, and 14, which can capture low or high dosage formulations depending on claim construction.
FAQs
1) Does US 4,387,089 require the presence of 2-ethylhexyl p-methoxycinnamate to infringe?
No. The UV-B partner is only required in specific dependent claims (notably Claims 3, 5, 8, 9, 13, and 17). Claim 2 and UV-A method/preparation claims can still apply without UV-B if the UV-A filter is present in an “effective” UV-absorbing amount.
2) If a product contains the UV-A filter but at 0.5 wt.%, what claims are most likely implicated?
Claim 4/5/12/13/16/17 concentration windows may not fit literally, but Claim 2 (composition) and Claims 10 and 14 (topical preparation and UV-A protection method) can still be asserted if the product is argued to contain an “effective” UV-absorbing amount.
3) Are process steps required for infringement under US 4,387,089?
No. Product claims (Claims 1, 2–5, 10–13) cover products, while process claims (Claims 6–9) are separate and require incorporation steps in cosmetic base formulations.
4) What is the cleanest “design-around” lever in this patent?
Replacing the UV-A filter molecule itself is the strongest lever because Claim 1 is compound-level. A secondary lever is removing the specific UV-B partner species used in the concentration-paired dependent claims (2-ethylhexyl p-methoxycinnamate).
5) Does the patent cover topical application methods specifically tied to UV-A?
Yes. Claims 14–17 are methods for protecting skin from effects of UV-A radiation through topical application of the UV-A absorber in a suitable carrier, with concentration and UV-B partnership limitations in dependent claims.
References
No references are included because the prompt provided only the claim text and did not provide bibliographic data, prosecution documents, or citation sources needed to comply with an evidence-based patent landscape analysis.
