Registry data as of Aug 27, 2026

William Isenberg, MD

Obstetrics & Gynecology Physician · Oakland, CA

William Isenberg, MD is an obstetrics & gynecology physician with a practice address in Oakland, California, and NPI 1265497101, issued on Apr 20, 2006. Check the license on the Medical Board of California; the federal record below is the public data PlainDoctor holds for this provider.

Record from CMS NPPES, loaded Aug 27, 2026 · method · Verify with CMS →

NPPES recordas of Aug 27, 2026
1265497101
Name
William Isenberg
Credential
MD
Primary taxonomy
Obstetrics & Gynecology Physician 207V00000X
Practice location
365 Hawthorne Ave, Oakland, CA 94609
Phone
(510) 893-1700
Enumerated
Apr 20, 2006
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). A record is not a license: verify it with the state board.
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Also registered at 365 Hawthorne Ave

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. David Anderson, MDInternal Medicine Physician1780613380
  2. Miranda Bassilios, PA CPhysician Assistant1609831114
  3. Edward Blumenstock, MDObstetrics & Gynecology Physician1235156738
  4. Gregory Broderick-Villa, MDSurgery Physician1376571562
  5. John Chiu, MDInterventional Cardiology Physician1629007000
  6. Stephen Etheredge, MDVascular Surgery Physician1770694101

Verify William Isenberg in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of CaliforniaCheck the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS, AOA, NCCPA, AANPNot checked
Open the California license search

PlainDoctor does not match the HHS-OIG exclusion list to individual records: most entries carry no NPI. Search the OIG exclusion list by name.

Statewide context: the Medical Board of California reported 374 disciplinary actions in FY 2022-23. California discipline data →

Obstetrics & Gynecology Physician providers in California

There are 5,004 obstetrics & gynecology physician records in California. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.

Other obstetrics & gynecology physician records in California

  1. Ingrid Aalami, MDSan Jose, CA1952376550
  2. Avisa Abaian- Eagar, M.D.Orange, CA1316057755
  3. Derek Abbassi, MDWalnut Creek, CA1841364155
  4. Nicole Abell, DOVentura, CA1811243603
  5. Zachary AbelsonLos Angeles, CA1689237414
  6. Sina Abhari, MDNewport Beach, CA1073955290
  7. Ray Abinader, M.D.Loma Linda, CA1770901548
  8. Tarek Abou El Kheir, M.D.San Bernardino, CA1477521789
  9. Nada Abou-HaibaLos Angeles, CA1134067549
  10. Ariel Abrahams, MDDowney, CA1376726174

Common questions

What is William Isenberg, MD's NPI number?

William Isenberg, MD's National Provider Identifier (NPI) is 1265497101, issued on Apr 20, 2006. An NPI identifies a provider in billing; it is not a license.

Where is William Isenberg, MD located?

The NPPES record lists a practice address at 365 Hawthorne Ave, Oakland, CA, 94609. Phone: (510) 893-1700. Providers update this record themselves, so call before visiting.

How can I verify William Isenberg, MD's license?

Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

Source: CMS National Plan and Provider Enumeration System (NPPES), loaded Aug 27, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. An NPI identifies who bills; it is not a license.

Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 27, 2026.