Robert J. Marx, MD
General Practice Physician · Los Gatos, CA
Robert J. Marx, MD is a general practice physician with a practice address in Los Gatos, California, and NPI 1073576351, issued on Apr 8, 2006. Check the license (California A30254, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Robert J. Marx
- Credential
- MD
- Primary taxonomy
- General Practice Physician 208D00000X
- License number
- A30254 CA
Self-reported in NPPES; status is on the state search - Practice location
- 14911 National Ave, Los Gatos, CA 95032
- Phone
- (408) 358-3511
- Enumerated
- Apr 8, 2006
- Record last updated
- Aug 31, 2010 (not updated in 16 years: call before relying on the address or phone)
- Fax
- (408) 358-0012
- Medicare enrollment
- Enrolled (PECOS I20100831000215); accepts Medicare assignment
- Medical or professional school
- Johns Hopkins University School Of Medicine, 1975
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest general practice physician records → All 1,956 in California → Look up another NPI →
Also registered at 14911 National Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Terence Delaney, MDSpecialist1205861226
- Sonya GonzalezHearing Instrument Specialist1699326835
- Mary Jane Hutchins, M.D.Internal Medicine Physician1134221583
- Janet Miles, AU.D.Hearing Instrument Specialist1578598538
- John Smith, MDCardiovascular Disease Physician1457346843
Verify Robert J. Marx in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A30254Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
57% fewer Medicare Part D claims than the average general practice physician in 2024
1,291 Medicare Part D claims for 163 beneficiaries, against an average of 3,030 among the 8,395 providers of this specialty who prescribed in Part D.
Most prescribed
- Atorvastatin Calcium212 claims
- Losartan Potassium102 claims
- Benazepril Hcl97 claims
- Amlodipine Besylate93 claims
- Levothyroxine Sodium93 claims
- Hydrochlorothiazide54 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.
Industry payments in 2024: $648.73
6 payments; by number, the most common kind was food and beverage; the largest payer was AstraZeneca Pharmaceuticals LP. The 4,259 providers of this specialty with any payment received $1,273.40 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.
Robert J. Marx among 1,956 general practice physician records in California
Robert J. Marx, MD is one of 1,956 general practice physician records with a practice address in California. 48% 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, 66% newer
- In a Medicare fileYes · 48% of these records are
- In the CMS Doctors and Clinicians fileYes · 27% of these records are
- Graduated1975 · median 1994 among the 520 with a school on file
- Record last updated2010 · 60% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 208D00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
General Practice Physician providers in California
There are 1,956 general practice physician records in California.
All 1,956 in California → Every provider in Los Gatos → General Practice Physician nationwide →
The 8 general practice physician records with the nearest ZIP codes
- Christopher Cirone, M.D.Los Gatos, CA 950321700105400
- Tuan Tran, D.O., D.C.Milpitas, CA 950351366467102
- Donna Nchekwube, MDMorgan Hill, CA 950371457324931
- Rick Eastin, M.D.Hollister, CA 950231376841999
- Michael Burry, M.D.Cupertino, CA 950141205286564
- Aye Aung, MDSanta Clara, CA 950511730672056
- Alex Im, MDSanta Clara, CA 950511285375980
- John Peterson, MDSanta Clara, CA 950511851419907
Common questions
What is Robert J. Marx, MD's NPI number?
Robert J. Marx, MD's National Provider Identifier (NPI) is 1073576351, issued on Apr 8, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Robert J. Marx, MD located?
The NPPES record lists a practice address at 14911 National Ave, Los Gatos, CA, 95032. Phone: (408) 358-3511. Providers update this record themselves, so call before visiting.
How can I verify Robert J. Marx, MD's license?
NPPES lists California license number A30254, 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 Robert J. Marx, MD prescribe under Medicare Part D?
In 2024, Robert J. Marx, MD had 1,291 Medicare Part D claims for 163 beneficiaries; the average among general practice physician prescribers was 3,030. 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.