Robert Warren, M.D.
Robert Warren, M.D. is a Surgery Physician in San Francisco, CA, registered under NPI 1336176015. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 1600 DIVISADERO ST 4TH FLOOR, San Francisco, CA 94143. 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 |
|---|---|---|
| G64251 | CA | Surgery Physician primary |
| G64251 | CA | Surgical Oncology Physician |
This provider holds licence G64251 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 Surgery covers
A general surgeon has expertise related to the diagnosis - preoperative, operative and postoperative management - and management of complications of surgical conditions in the following areas: alimentary tract; abdomen; breast, skin and soft tissue; endocrine system; head and neck surgery; pediatric surgery; surgical critical care; surgical oncology; trauma and burns; and vascular surgery. General surgeons increasingly provide care through the use of minimally invasive and endoscopic techniques. Many general surgeons also possess expertise in transplantation surgery, plastic surgery and cardiothoracic surgery. NUCC Health Care Provider Taxonomy, code 208600000X
All registered taxonomy codes
This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 208600000X | Surgery Physician | G64251 | CA | primary |
| 2086X0206X | Surgical Oncology Physician Surgical Oncology | G64251 | CA |
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 | 1336176015 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jun 27, 2006 |
| Last updated | Jun 16, 2008 |
| Status | Active |
| Sole proprietor | No |
| Credential | M.D. |
| Practice address |
1600 DIVISADERO ST 4TH FLOOR San Francisco, CA 94143 (415) 353-9889 Fax (415) 353-9958 |
| Mailing address |
1635 DIVISADERO STREET SUITE 625, BOX 1821 San Francisco, CA 94143 |
| Other identifiers |
00G642510
· Medicaid (CA) |
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 | 3 | 6 | 1 | 7 | 6 | 0 | 1 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 3 | 6 | 6 | 2 | 7 | 3 | 0 | 2 |
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.