Gary Marsh, M.D.
NPI 1639116296 · Cardiovascular Disease Physician · Downey, CA
Enrolled with Medicare as Order and Referring Only - Cardiovascular Disease (cardiology) · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Gary Marsh, M.D. is a Cardiovascular Disease Physician provider in Downey, CA (NPI 1639116296).
Provider details
- NPI number
- 1639116296
- Entity type
- Individual
- Primary specialty
- Cardiovascular Disease PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- A20613 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
20 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-06-01
- Last updated
- 2011-07-29
Frequently asked questions
- What is Gary Marsh's NPI number?
- Gary Marsh's National Provider Identifier (NPI) is 1639116296, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Gary Marsh's specialty?
- Gary Marsh is listed in the NPPES registry with a primary specialty of Cardiovascular Disease Physician (Allopathic & Osteopathic Physicians).
- Where is Gary Marsh located?
- Gary Marsh's practice location on file with NPPES is 9040 Telegraph Rd, Downey, CA 90240-2393.
- What is Gary Marsh's phone number?
- The practice phone number listed in the NPPES registry for Gary Marsh is (562) 861-0954.
- Does Gary Marsh accept Medicare?
- Gary Marsh is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Gary Marsh's NPI active?
- Yes — Gary Marsh's NPI (1639116296) is active in the NPPES registry as of the last update on 2011-07-29.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.