Listed as a CPA in IRS public preparer records. Source: IRS PTIN FOIA extract (Feb 2026), retrieved October 23, 2026. https://www.irs.gov/pub/foia/foia-california-extract.csv No state license number is on file. Specialties are blank until this preparer claims the listing. CPA Seek does not contact preparers.

Frank Mario Castellon

CPA · Castellon Professional Services PC

Sunnyvale, California 94086

Frank Mario Castellon, CPA in Sunnyvale, CA

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Frank Mario Castellon, CPA in Sunnyvale · CPA Seek