Stephen Greene, M.D.
Stephen Greene, M.D. is an Occupational Medicine Physician in Lancaster, CA, registered under NPI 1659577823. This provider registers 4 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 43835 10TH STREET WEST, Lancaster, CA 93534. 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 |
|---|---|---|
| A44065 | CA | Occupational Medicine Physician primary |
| A44065 | CA | Internal Medicine Physician |
| A44065 | CA | Preventive Medicine/Occupational… |
| A44065 | CA | Legal Medicine (M.D./D.O.) Physician |
This provider holds licence A44065 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 Occupational Medicine covers
Occupational medicine focuses on the health of workers, including the ability to perform work; the physical, chemical, biological, and social environments of the workplace; and the health outcomes of environmental exposures. Practitioners in this field address the promotion of health in the work place, and the prevention and management of occupational and environmental injury, illness, and disability. NUCC Health Care Provider Taxonomy, code 2083X0100X
All registered taxonomy codes
This provider registers 4 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 2083X0100X | Occupational Medicine Physician Occupational Medicine | A44065 | CA | primary |
| 207R00000X | Internal Medicine Physician | A44065 | CA | |
| 2083P0500X | Preventive Medicine/Occupational Environmental Medicine Physician Preventive Medicine/Occupational Environmental Medicine | A44065 | CA | |
| 209800000X | Legal Medicine (M.D./D.O.) Physician | A44065 | 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 | 1659577823 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jun 25, 2007 |
| Last updated | Sep 11, 2025 |
| Status | Active |
| Sole proprietor | No |
| Credential | M.D. |
| Practice address |
43835 10TH STREET WEST Lancaster, CA 93534 (661) 945-5999 Fax (661) 948-2897 |
| Mailing address |
1230 W 3RD ST Los Angeles, CA 90017 |
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 | 6 | 5 | 9 | 5 | 7 | 7 | 8 | 2 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 6 | 1 | 9 | 1 | 7 | 5 | 8 | 4 |
Sum = 67 · next multiple of 10 = 70 · check digit = 3 · actual last digit = 3
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.