Mark Wellisch, M.D.
Mark Wellisch, M.D. is a Sports Medicine (Orthopaedic Surgery) Physician in Encino, CA, registered under NPI 1982685996. This provider registers 3 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 16311 VENTURA BLVD SUITE 800, Encino, CA 91436. 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 |
|---|---|---|
| A23373 | CA | Sports Medicine (Orthopaedic Surgery)… primary |
| A23373 | CA | Orthopaedic Surgery Physician |
| A23373 | CA | Pediatric Sports Medicine Physician |
This provider holds licence A23373 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 Sports Medicine covers
An orthopaedic surgeon trained in sports medicine provides appropriate care for all structures of the musculoskeletal system directly affected by participation in sporting activity. This specialist is proficient in areas including conditioning, training and fitness, athletic performance and the impact of dietary supplements, pharmaceuticals, and nutrition on performance and health, coordination of care within the team setting utilizing other health care professionals, field evaluation and management, soft tissue biomechanics and injury healing and repair. Knowledge and understanding of the principles and techniques of rehabilitation, athletic equipment and orthotic devices enables the specialist to prevent and manage athletic injuries. NUCC Health Care Provider Taxonomy, code 207XX0005X
All registered taxonomy codes
This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 207XX0005X | Sports Medicine (Orthopaedic Surgery) Physician Sports Medicine | A23373 | CA | primary |
| 207X00000X | Orthopaedic Surgery Physician | A23373 | CA | |
| 2080S0010X | Pediatric Sports Medicine Physician Sports Medicine | A23373 | 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 | 1982685996 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Nov 7, 2005 |
| Last updated | Sep 11, 2025 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | M.D. |
| Practice address |
16311 VENTURA BLVD SUITE 800 Encino, CA 91436 (818) 788-7343 Fax (818) 788-9453 |
| Other identifiers |
00A233730
· 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 | 9 | 8 | 2 | 6 | 8 | 5 | 9 | 9 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 9 | 7 | 2 | 3 | 8 | 1 | 9 | 9 |
Sum = 74 · next multiple of 10 = 80 · check digit = 6 · actual last digit = 6
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.