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NINTH AVENUE INTERNAL MEDICINE LLC
NPI 1639181126
Clinic/Center - Health Service in Denver, CO

Active since August 12, 2006CLIA 06D1015598 · Waiver
4500 E 9TH AVE, SUITE 140, DENVER, CO 80220(303) 394-2152(303) 394-2496 Get Directions Write a Review

NPPES record last updated: September 24, 2007. Verified against the NPPES registry weekly; last sync: November 01, 2026.

About Ninth Avenue Internal Medicine Llc NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

NINTH AVENUE INTERNAL MEDICINE LLC (NPI 1639181126) is a healthcare organization registered as a health service in Denver, Colorado and active in the NPI registry since August 2006. The organization holds a CLIA Waiver certificate valid through August 10, 2027 and lists Daniel Witten, Managing Partner, as its authorized official.

NPPES Registry Identity

NPI1639181126
Entity TypeOrganization
Primary Taxonomy261QH0100X
Legal Business NameNINTH AVENUE INTERNAL MEDICINE LLC
Location Address4500 E 9TH AVE, SUITE 140Denver, CO 80220-3900
Mailing Address4500 E 9th Ave, Suite 140Denver, CO 80220-3900 · (303) 394-2152 · Fax (303) 394-2496
Phone(303) 394-2152
Fax(303) 394-2496
Organization SubpartNo
Authorized OfficialDaniel WittenManaging Partner · (303) 394-2152
Enumeration DateAugust 12, 2006
Last NPPES UpdateSeptember 24, 2007
✔ NPI 1639181126 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyClinic/Center · Health ServiceAmbulatory Health Care Facilities
Taxonomy Code261QH0100X
4500 E 9TH AVE, Denver, CO 80220
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Other Identifiers 2

Medicaid73100374CO
Medicare ID-Type Unspecified503838

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Ninth Avenue Internal Medicine Llc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

2

Medicare enrollment records show 2 clinicians reassign Medicare billing to Ninth Avenue Internal Medicine LLC, which bills Medicare for the services they deliver. Of these, 2 practice at this address. They are listed nearest first.

Clinicians, nearest first (2)

Igor Borisov, MD
Internal Medicine
NPI 1235134008
4500 E 9TH AVE STE 140
Denver, CO 80220
(303) 394-2152
✔ PECOS✔ Accepts MedicareSame address
Daniel Witten, MD
Internal Medicine
NPI 1245233782
4500 E 9TH AVE STE 140
Denver, CO 80220
(303) 394-2152
✔ PECOS✔ Accepts MedicareSame address

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

CLIA Laboratory Certificates CMS CLIA

Laboratory certificates issued under the Clinical Laboratory Improvement Amendments (CLIA) program, which sets federal quality standards for human laboratory testing in the United States. There is no official CMS crosswalk between CLIA and NPI numbers; these certificates are associated with this NPI by matching facility names, locations and phone numbers in the CMS CLIA registry.

Certificate of Waiver 06D1015598

Ninth Avenue Internal Medicine, LLC · Denver, CO
Active · expires Aug 10, 2027
CLIA Number06D1015598
Laboratory TypePhysician Office
Certificate Effective DateAugust 11, 2025
Certificate Expiration DateAugust 10, 2027
Laboratory DirectorDr. Daniel Witten
Laboratory Phone(303) 394-2152
Laboratory LocationNinth Avenue Internal Medicine, LLC4500 E 9th Ave, Suite 140, Denver, CO 80220
CLIA data matches this NPI record on: Address Name Phone
This certificate is issued to a laboratory to perform only waived tests.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Ninth Avenue Internal Medicine LLC's NPI number?

The NPI number for Ninth Avenue Internal Medicine LLC is 1639181126. It was assigned to this organization in the NPPES registry on August 12, 2006.

Where is Ninth Avenue Internal Medicine LLC located?

Ninth Avenue Internal Medicine LLC is located at 4500 E 9th Ave Suite 140, Denver, CO 80220. The listed phone number is (303) 394-2152.

What is Ninth Avenue Internal Medicine LLC's specialty?

The primary specialty registered for this NPI is Clinic/Center, specializing in Health Service, with taxonomy code 261QH0100X.

Is Ninth Avenue Internal Medicine LLC enrolled in Medicare?

Yes. Ninth Avenue Internal Medicine LLC is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Ninth Avenue Internal Medicine LLC?

According to the CMS Revalidation Reassignment List (October 2026 release), 2 clinicians, all in Internal Medicine, reassign their Medicare billing to Ninth Avenue Internal Medicine LLC. A reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for the clinician's services. Of these, 2 practice at this address. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Does Ninth Avenue Internal Medicine LLC hold a CLIA laboratory certificate?

Yes. A Certificate of Waiver (number 06D1015598) is associated with this NPI, valid through August 10, 2027. CLIA certificates authorize laboratory testing under the federal Clinical Laboratory Improvement Amendments program.

When was this NPI record last updated?

The NPPES record for Ninth Avenue Internal Medicine LLC was last updated on September 24, 2007. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.