Diane Sun, M.D.
NPI 1962527952 · Internal Medicine Physician · Hayward, CA
Enrolled with Medicare as Practitioner - Allergy/Immunology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Diane Sun, M.D. is a Internal Medicine Physician provider in Hayward, CA (NPI 1962527952).
Provider details
- NPI number
- 1962527952
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Female
- Sole proprietor
- No
- License
- 0101247713 (VA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Student, Health Care
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 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
- 2007-03-20
- Last updated
- 2021-12-15
Frequently asked questions
- What is Diane Sun's NPI number?
- Diane Sun's National Provider Identifier (NPI) is 1962527952, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Diane Sun's specialty?
- Diane Sun is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Diane Sun located?
- Diane Sun's practice location on file with NPPES is 27303 Sleepy Hollow Ave S, Hayward, CA 94545-4203.
- What is Diane Sun's phone number?
- The practice phone number listed in the NPPES registry for Diane Sun is (510) 454-1000.
- Does Diane Sun accept Medicare?
- Diane Sun is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Diane Sun's NPI active?
- Yes — Diane Sun's NPI (1962527952) is active in the NPPES registry as of the last update on 2021-12-15.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.