Alexander Marson, M.D., PH.D.
Internal Medicine Physician · San Francisco, CA
Alexander Marson, M.D., PH.D. is an internal medicine physician with a practice address in San Francisco, California, and NPI 1417276254, issued on May 19, 2010. Check the license (California A121580, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Alexander Marson
- Credential
- M.D., PH.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- A121580 CA
Self-reported in NPPES; status is on the state search - Practice location
- 400 Parnassus Ave, San Francisco, CA 94143
- Phone
- (415) 353-2326
- Enumerated
- May 19, 2010
- Record last updated
- Mar 25, 2015 (not updated in 11 years: call before relying on the address or phone)
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
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Verify Alexander Marson in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A121580Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Industry payments in 2024: $13,414.45
8 payments; by number, the most common kind was travel and lodging; the largest payer was Amgen Inc. The 50,334 providers of this specialty with any payment received $1,303.06 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.
Alexander Marson among 17,696 internal medicine physician records in California
Alexander Marson, M.D., PH.D. 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 2010, is newer than 63% of them.
- NPI issued2010 · 63% of these records are older, 34% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileNo · 63% of these records are
- Record last updated2015 · 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 →
The 8 internal medicine physician records with the nearest ZIP codes
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- John Kane, MDSan Francisco, CA 941431467416461
- Suneil Koliwad, M.D., PH.D.San Francisco, CA 941431225006687
- Bernard Lo, MDSan Francisco, CA 941431184688137
- Stephen McPhee, MDSan Francisco, CA 941431124082490
- Andrew Posselt, MDSan Francisco, CA 941431235193616
Common questions
What is Alexander Marson, M.D., PH.D.'s NPI number?
Alexander Marson, M.D., PH.D.'s National Provider Identifier (NPI) is 1417276254, issued on May 19, 2010. An NPI identifies a provider in billing; it is not a license.
Where is Alexander Marson, M.D., PH.D. located?
The NPPES record lists a practice address at 400 Parnassus Ave, San Francisco, CA, 94143. Phone: (415) 353-2326. Providers update this record themselves, so call before visiting.
How can I verify Alexander Marson, M.D., PH.D.'s license?
NPPES lists California license number A121580, 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.
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.