Frederic Grannis, MD
Frederic Grannis, MD is a Thoracic Surgery (Cardiothoracic Vascular Surgery) Physician in Duarte, CA, registered under NPI 1598773582. 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 1500 E DUARTE RD, Duarte, CA 91010. 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 |
|---|---|---|
| G36693 | CA | Thoracic Surgery (Cardiothoracic Vascular… primary |
| G36693 | CA | Surgical Oncology Physician |
This provider holds licence G36693 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 Thoracic Surgery (Cardiothoracic Vascular Surgery) covers
A thoracic surgeon provides the operative, perioperative and critical care of patients with pathologic conditions within the chest. Included is the surgical care of coronary artery disease, cancers of the lung, esophagus and chest wall, abnormalities of the trachea, abnormalities of the great vessels and heart valves, congenital anomalies, tumors of the mediastinum and diseases of the diaphragm. The management of the airway and injuries of the chest is within the scope of the specialty. NUCC Health Care Provider Taxonomy, code 208G00000X
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 | |
|---|---|---|---|---|
| 208G00000X | Thoracic Surgery (Cardiothoracic Vascular Surgery) Physician | G36693 | CA | primary |
| 2086X0206X | Surgical Oncology Physician Surgical Oncology | G36693 | 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 | 1598773582 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Aug 4, 2006 |
| Last updated | Aug 11, 2015 |
| Status | Active |
| Sole proprietor | No |
| Credential | MD |
| Practice address |
1500 E DUARTE RD Duarte, CA 91010 (626) 359-8111 |
| Mailing address |
1333 S. MAYFLOWER AVE., 2ND FLOOR Monrovia, CA 91016 |
| Other identifiers |
00G386930
· 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 | 9 | 8 | 7 | 7 | 3 | 5 | 8 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 5 | 9 | 8 | 5 | 7 | 6 | 5 | 7 |
Sum = 78 · next multiple of 10 = 80 · check digit = 2 · actual last digit = 2
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.