Marilyn Welch, RN
Marilyn Welch, RN is a provider specialising in Skilled Nursing Facility in Menlo Park, CA, registered under NPI 1205850625. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty. 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 795 WILLOW RD, Menlo Park, CA 94025. 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 |
|---|---|---|
| 194238 | CA | Registered Nurse |
This provider holds licence 194238 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 Skilled Nursing Facility covers
(1) A skilled nursing facility is a facility or distinct part of an institution whose primary function is to provide medical, continuous nursing, and other health and social services to patients who are not in an acute phase of illness requiring services in a hospital, but who require primary restorative or skilled nursing services on an inpatient basis above the level of intermediate or custodial care in order to reach a degree of body functioning to permit self care in essential daily living. It meets any licensing or certification standards et forth by the jurisdiction where it is located. A skilled nursing facility may be a freestanding facility or part of a hospital that has been certified by Medicare to admit patients requiring subacute care and rehabilitation; (2) Provides non-acute medical and skilled nursing care services, therapy and social services under the supervision of a licensed registered nurse on a 24-hour basis. NUCC Health Care Provider Taxonomy, code 314000000X
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 | |
|---|---|---|---|---|
| 314000000X | Skilled Nursing Facility | — | — | primary |
| 163W00000X | Registered Nurse | 194238 | 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 | 1205850625 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jul 27, 2006 |
| Last updated | Sep 11, 2025 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | RN |
| Practice address |
795 WILLOW RD Menlo Park, CA 94025 (650) 493-5000 Fax (650) 614-9852 |
| Mailing address |
843 BARCELONA DR Fremont, CA 94536 |
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 | 2 | 0 | 5 | 8 | 5 | 0 | 6 | 2 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 2 | 0 | 5 | 7 | 5 | 0 | 6 | 4 |
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.