Registered patent attorney

Leon M. Cao

USPTO Reg. 83952

Firm

Banner & Witcoff

Address

71 S Wacker Dr

#3600

Chicago, IL, 60606

US

Phone

Registered as

Registered patent attorney

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Frequently asked

Frequently asked about Leon M. Cao

  • Is Leon M. Cao a registered patent attorney?

    Yes. Leon M. Cao is a registered patent attorney with the United States Patent and Trademark Office (USPTO Registration Number 83952). Registration is verified against the USPTO Office of Enrollment and Discipline roster.

  • Where is Leon M. Cao located?

    Leon M. Cao's office is in Chicago, Illinois (60606). Affiliated with Banner & Witcoff.

  • What firm does Leon M. Cao work at?

    Leon M. Cao is listed as affiliated with Banner & Witcoff on the USPTO Office of Enrollment and Discipline practitioner roster.

  • How do I contact Leon M. Cao?

    Leon M. Cao's office phone (per the USPTO public roster) is 312-463-5461. Verify availability and intake details directly with the firm before sending privileged materials.

  • Should I prepare anything before contacting a patent attorney?

    Yes — most patent attorneys quote based on a brief. Persoona's intellectual property module generates a prior-art analysis, defensibility scorecard, and a draft USPTO filing package so you arrive with a brief, not a blank slate. Free to run.

Profile sourced from the USPTO OEDCI Practitioner Roster. Persoona did not provide, edit, or curate this data — every field is pulled directly from the public roster.

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