Margaret C. Fang, MD
Internal Medicine Physician · San Francisco, CA
Margaret C. Fang, MD is an internal medicine physician with a practice address in San Francisco, California, and NPI 1417911462, issued on Apr 14, 2006. Check the license (California A83381, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Margaret C. Fang
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- A83381 CA
Self-reported in NPPES; status is on the state search - Practice location
- 533 Parnassus Ave, San Francisco, CA 94143
- Phone
- (415) 502-1414
- Enumerated
- Apr 14, 2006
- Record last updated
- Jul 30, 2008 (not updated in 18 years: call before relying on the address or phone)
- Fax
- (415) 514-2094
- Medicaid ID
- 0A8338100 CA
- Medicare enrollment
- Enrolled (PECOS I20080225000603); accepts Medicare assignment
- Medical or professional school
- Northwestern University Feinberg Medical School, 1998
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 533 Parnassus Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- David DarevskyStudent in an Organized Health Care Education/Training Program1871351171
Verify Margaret C. Fang in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A83381Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
90% fewer Medicare Part D claims than the average internal medicine physician in 2024
312 Medicare Part D claims for 122 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 21% of claims.
Most prescribed
- Warfarin Sodium198 claims
- Eliquis56 claims
- Enoxaparin Sodium15 claims
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.
The practice group's MIPS final score for 2023 (Medicare payment program): 74.5 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
Bills Medicare through 3 group practices
- Regents OF The University OF CaliforniaSan Francisco, CA
- Ucsf Medical Group Business ServicesBurlingame, CA
- University OF California San FranciscoSan Francisco, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Margaret C. Fang among 17,696 internal medicine physician records in California
Margaret C. Fang, MD is one of 17,696 internal medicine physician records with a practice address in California. 79% 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, 56% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated1998 · median 2004 among the 11,065 with a school on file
- Record last updated2008 · 61% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
1,318 internal medicine physician records list a practice address in San Francisco
They are 1,318 of the 38,143 NPPES records with a practice address in San Francisco, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in San Francisco → Internal Medicine Physician nationwide →
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Common questions
What is Margaret C. Fang, MD's NPI number?
Margaret C. Fang, MD's National Provider Identifier (NPI) is 1417911462, issued on Apr 14, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Margaret C. Fang, MD located?
The NPPES record lists a practice address at 533 Parnassus Ave, San Francisco, CA, 94143. Phone: (415) 502-1414. Providers update this record themselves, so call before visiting.
How can I verify Margaret C. Fang, MD's license?
NPPES lists California license number A83381, 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 Margaret C. Fang, MD prescribe under Medicare Part D?
In 2024, Margaret C. Fang, MD had 312 Medicare Part D claims for 122 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
What is Margaret C. Fang, MD's MIPS final score?
The 2023 MIPS final score is 74.5 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.
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.