William Joseph, M.D.
William Joseph, M.D. is an Infectious Disease Physician in San Ramon, CA, registered under NPI 1356423255. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 5601 NORRIS CANYON RD SUITE #220, San Ramon, CA 94583. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| G27536 | CA | Infectious Disease Physician primary |
This provider holds licence G27536 issued in CA. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
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 Infectious Disease covers
An internist who deals with infectious diseases of all types and in all organ systems. Conditions requiring selective use of antibiotics call for this special skill. This physician often diagnoses and treats AIDS patients and patients with fevers which have not been explained. Infectious disease specialists may also have expertise in preventive medicine and travel medicine. NUCC Health Care Provider Taxonomy, code 207RI0200X
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-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1356423255 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Oct 19, 2006 |
| Last updated | Apr 19, 2022 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | M.D. |
| Practice address |
5601 NORRIS CANYON RD SUITE #220 San Ramon, CA 94583 (925) 277-2050 Fax (925) 275-1018 |
| Mailing address |
12677 ALCOSTA BLVD STE 378 San Ramon, CA 94583 |
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 | 3 | 5 | 6 | 4 | 2 | 3 | 2 | 5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 3 | 1 | 6 | 8 | 2 | 6 | 2 | 1 |
Sum = 55 · next multiple of 10 = 60 · check digit = 5 · actual last digit = 5
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.