CORE DIAGNOSTICS INC.
CORE DIAGNOSTICS INC. is an organization registered with the National Plan and Provider Enumeration System (NPPES) under NPI 1003128646, based in Hayward, CA. It is classified under Clinical Medical Laboratory.
Getting there
Here is what surrounds this office in Hayward, based on OpenStreetMap data collected Sep 7, 2026. Parking is available about 0.50 mi away. The nearest transit stop is 1,024 ft away, served by 25823 Clawiter Road.
Getting here and what is nearby
Transit Clawiter Road & Breakwater Avenue 378 ft ~2 min
Transit Clawiter Road & Breakwater Avenue 524 ft ~2 min
Transit 25823 Clawiter Road 1,024 ft ~4 min
Parking 0.50 mi ~10 min
Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.
Credentials and Medicare
NPPES does not list a state licence number for this record. That is not unusual — organizations and some provider types are not required to file one. Verify current licensure with the relevant state board before care.
This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.
What Clinical Medical Laboratory covers
(1) A clinical laboratory is a facility for the biological, microbiological, serological, chemical, immunohematological, hematological, biophysical, cytological, pathological, or other examination of materials derived from the human body for the purpose of providing information for the diagnosis, prevention, or treatment of any disease or impairment of, human beings. These examinations also include procedures to determine, measure, or otherwise describe the presence or absence of various substances or organisms in the body. Facilities only collecting or preparing specimens (or both) or only serving as a mailing service and not performing testing are not considered clinical laboratories. (2) Any facility that examines materials from the human body for purposes of providing information for the diagnosis, prevention, or treatment of any disease or impairment of, or the assessment of, the health of human beings. Typical divisions of a clinical laboratory include hematology, cytology, bacteriology, histology, biochemistry, medical toxicology, and serology. NUCC Health Care Provider Taxonomy, code 291U00000X
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-2 identifies an organization — a clinic, hospital, group practice, laboratory, or supplier. Individual clinicians working there hold their own NPI-1 numbers separately, so a bill may reference both.
| NPI | 1003128646 valid check digit |
|---|---|
| Entity type | Organization (NPI-2) |
| Enumeration date | Jul 12, 2010 |
| Last updated | Jan 31, 2017 |
| Status | Active |
| Practice address |
3535 BREAKWATER AVE Hayward, CA 94545 (650) 532-9500 Fax (650) 532-9550 |
| Other names |
Oncomdx Inc. Professional Name |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 0 | 0 | 3 | 1 | 2 | 8 | 6 | 4 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 0 | 3 | 2 | 2 | 7 | 6 | 8 |
Sum = 54 · next multiple of 10 = 60 · check digit = 6 · actual last digit = 6
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.