William Edward Rietkerk, MD MBA
Dermatology · Thousand Oaks, CA
At a glance
55 Rolling Oaks Dr Ste 200, Thousand Oaks, CA 91361-1010
Published activity: Melanoma (skin cancer) excision · Removal of skin lesions · Skin biopsy. View counts and coverage
NPPES record updated Jul 21, 2022. Public records can lag behind changes at a practice.
Before you call: a quick checklist
- Are you accepting new patients?
- Do you accept my specific insurance plan?
- Do you provide the service I need at this address?
- Do I need a referral, and what is the earliest appointment?
Insurance participation and appointment availability are not established by these public records.
Medicare & insurance
Insurance participation is not established by these public records. Ask the practice and your insurer about your specific plan and this location.
How to check your coverage
Use your plan’s provider directory or the member-services number on your insurance card. Confirm the clinician, practice address, service, and whether a referral is required. A missing opt-out record does not establish Medicare acceptance.
Check the official Medicare directory ↗Practice location
55 Rolling Oaks Dr Ste 200Thousand Oaks, CA 91361-1010
Education & affiliations
- Medical / professional school
- University Of California, Irvine, California College Of Medicine
- Graduation year
- 2008
- CMS specialties
- Dermatology
Practice groups
Graduation year does not establish years in practice. A reported affiliation does not establish employment, current admitting privileges, or insurance participation.
Source: CMS National Downloadable File · Published Oct 15, 2026.
Procedures in the public data
Reported activity can help you ask more informed questions about a practice’s services.
| Procedure category | Published Medicare activity |
|---|---|
| Melanoma (skin cancer) excision | 69 |
| Removal of skin lesions | 3495 |
| Skin biopsy | 716 |
CMS uses a one-year claims window with a reporting lag. Counts cover the Medicare activity included by CMS, not all patients. “1–10” is a published range. Volume is not a quality or outcomes score. Coverage and methodology
Source: CMS Utilization Data · Published Oct 15, 2026.
Find providers with a similar service mix
Compare 2024 published Medicare activity in the same reported specialty, here or in another city.
Industry-reported general payments
Includes reported transfers of value, such as meals, travel, or consulting. Payments do not establish improper conduct or quality of care. Research funding and ownership values are excluded from this total.
See payment purposes and reporting companies
Reported purposes
| Purpose | Amount |
|---|---|
| Consulting fee | $1,950.00 |
| Food and beverage | $1,693.79 |
| Education | $184.65 |
Reporting companies
| Company | Amount |
|---|---|
| UCB, INC. | $2,125.19 |
| REGENERON HEALTHCARE SOLUTIONS, INC. | $372.56 |
| SUN PHARMACEUTICAL INDUSTRIES INC. | $250.68 |
| JANSSEN BIOTECH, INC. | $184.76 |
| LEO PHARMA INC. | $150.58 |
| GALDERMA LABORATORIES, L.P. | $126.04 |
| LILLY USA, LLC | $92.66 |
| ABBVIE INC. | $81.44 |
| Other reporting companies | $444.53 |
Source: CMS 2025 payments grouped by covered recipient and nature of payments · Published Jun 30, 2026.
Professional details: NPI, taxonomy & registry record
Registry details
- Primary taxonomy
- Dermatology
- Taxonomy code
- 207N00000X
- Enumeration date
- Sep 11, 2009
- Record updated
- Jul 21, 2022
More registry details
- Provider type
- Individual · Type 1
- Reported credentials
- MD MBA
Reported taxonomies and licenses
207N00000X · Primary
License reported: A141249 CA
License numbers and credentials are reported to NPPES; HCPList does not independently verify them.
Practice location
55 Rolling Oaks Dr Ste 200Thousand Oaks, CA 91361-1010
- Phone
- (212) 661-3376
- Fax
- (212) 661-3366
Mailing address
55 ROLLING OAKS DRIVESUITE 200
THOUSAND OAKS, CA 91361
Information may be outdated or incomplete. Confirm details directly with the practice. HCPList is an independent directory and is not affiliated with CMS.
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