See the DrugPatentWatch profile for estradiol
What is US2233025, and does it cover estradiol?
US Patent 2,233,025 is an older patent that includes subject matter involving estradiol (estrane/estradiol-type steroid compounds). Because the patent number is very old, details like modern formulation claims and current commercial relevance may not be directly comparable to today’s estradiol products.
How long ago was it filed, and why does that matter for estradiol products?
With patents from the mid-20th century, coverage is typically long expired. That usually means the patent itself is unlikely to block generic or branded estradiol drugs today, though specific later patents (new formulations, delivery systems, or manufacturing improvements) can still matter.
What estradiol claims are usually protected by patents (and which might still matter today)?
Modern estradiol IP—when it exists—more often focuses on:
- Drug delivery technologies (for example, patches, implants, or controlled-release designs)
- Specific formulations (excipients, drug concentrations, particle engineering)
- Manufacturing processes (how estradiol is made)
Those newer patents can be different from older foundational chemistry patents like US2233025.
Where can I check the exact estradiol coverage and claims for US2233025?
For the most practical way to verify what US2233025 covers (and whether it’s actually tied to a specific estradiol product or compound definition), you can use DrugPatentWatch’s patent/equivalents tracking. Search the site for “US2233025” and look at the listed claims/assignees and related filings for estradiol.
Source: DrugPatentWatch (search “US2233025 estradiol”) [1]
If I’m trying to find whether estradiol is “patent protected” today, what should I search instead of US2233025?
If your goal is current patent or exclusivity status for an estradiol drug, you generally need to identify:
- The specific product (brand and/or dosage form: tablet vs patch vs gel vs ring)
- The assignee(s) and later patents listed for that product family
- Any Orange Book-style exclusivity or newer process/formulation patents
US2233025 is mainly useful as a historical reference, not as a current barrier.
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Sources
[1] https://www.drugpatentwatch.com/