Maria C. Quan, MD
Obstetrics & Gynecology Physician · San Ramon, CA
Maria C. Quan, MD is an obstetrics & gynecology physician with a practice address in San Ramon, California, and NPI 1043281405, issued on Feb 1, 2006. Check the license (California C143703, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Maria C. Quan
- Credential
- MD
- Primary taxonomy
- Obstetrics & Gynecology Physician 207V00000X
- License numbers
- C143703 CA
MD00037841 WA
Self-reported in NPPES; status is on the state search - Practice location
- 11030 Bollinger Canyon RD Ste 200, San Ramon, CA 94582
- Phone
- (925) 263-5583
- Enumerated
- Feb 1, 2006
- Record last updated
- May 18, 2026
- Medicaid ID
- 8245193 WA
- Medicare enrollment
- Enrolled (PECOS I20220131000894); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest obstetrics & gynecology physician records → All 5,088 in California → Look up another NPI →
Also registered at 11030 Bollinger Canyon RD Ste 200
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Valerie PetersFamily Nurse Practitioner1447672027
Verify Maria C. Quan in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license C143703Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
84% fewer Medicare Part D claims than the average obstetrics & gynecology physician in 2024
27 Medicare Part D claims, against an average of 165 among the 28,733 providers of this specialty who prescribed in Part D.
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Industry payments in 2024: $25.71
1 payment: food and beverage; the largest payer was Astellas Pharma US Inc. The 21,429 providers of this specialty with any payment received $1,030.61 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through 2 group practices
- University Healthcare AllianceCastro Valley, CA
- Vista Community ClinicVista, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Maria C. Quan among 5,088 obstetrics & gynecology physician records in California
Maria C. Quan, MD is one of 5,088 obstetrics & gynecology physician records with a practice address in California. 74% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 5% of them.
- NPI issued2006 · 5% of these records are older, 52% newer
- In a Medicare fileYes · 74% of these records are
- In the CMS Doctors and Clinicians fileYes · 53% of these records are
- Graduated1989 · median 2004 among the 2,700 with a school on file
- Record last updated2026 · 64% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207V00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Obstetrics & Gynecology Physician providers in California
There are 5,088 obstetrics & gynecology physician records in California.
All 5,088 in California → Every provider in San Ramon → Obstetrics & Gynecology Physician nationwide →
The 8 obstetrics & gynecology physician records with the nearest ZIP codes
- Ravi Agarwal, MDSan Ramon, CA 945831710331236
- Curtis Appel, MDSan Ramon, CA 945831831279314
- Emil Eyvazzadeh, MDSan Ramon, CA 945831881702462
- Renee Hilliard, M.D.San Ramon, CA 945831245265065
- Leroy Leabman, MDSan Ramon, CA 945831598041360
- Mark Lollar, MDSan Ramon, CA 945831124119623
- Helen Matthews, M.D.San Ramon, CA 945831013015627
- Cassandra MellingerSan Ramon, CA 945831811647803
Common questions
What is Maria C. Quan, MD's NPI number?
Maria C. Quan, MD's National Provider Identifier (NPI) is 1043281405, issued on Feb 1, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Maria C. Quan, MD located?
The NPPES record lists a practice address at 11030 Bollinger Canyon RD Ste 200, San Ramon, CA, 94582. Phone: (925) 263-5583. Providers update this record themselves, so call before visiting.
How can I verify Maria C. Quan, MD's license?
NPPES lists California license number C143703, as entered by the provider. 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.
How much does Maria C. Quan, MD prescribe under Medicare Part D?
In 2024, Maria C. Quan, MD had 27 Medicare Part D claims; the average among obstetrics & gynecology physician prescribers was 165. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.