Robert Messing, M.D.
Robert Messing, M.D. is a Neurology Physician in San Francisco, CA, registered under NPI 1558487348.
Getting there
The practice address on file is 1001 POTRERO AVE, 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 |
|---|---|---|
| G46801 | CA | Neurology Physician primary |
This provider holds licence G46801 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 Neurology covers
A Neurologist specializes in the diagnosis and treatment of diseases or impaired function of the brain, spinal cord, peripheral nerves, muscles, autonomic nervous system, and blood vessels that relate to these structures. NUCC Health Care Provider Taxonomy, code 2084N0400X
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 | 1558487348 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Mar 22, 2007 |
| Last updated | Jul 9, 2007 |
| Status | Active |
| Sole proprietor | No |
| Credential | M.D. |
| Practice address |
1001 POTRERO AVE San Francisco, CA 94143 (415) 206-8297 |
| Mailing address |
5858 HORTON ST SUITE 200 Emeryville, CA 94608 |
| Other identifiers |
GR0024313
· 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 | 5 | 5 | 8 | 4 | 8 | 7 | 3 | 4 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 5 | 1 | 8 | 8 | 8 | 5 | 3 | 8 |
Sum = 72 · next multiple of 10 = 80 · check digit = 8 · actual last digit = 8
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.