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Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

ALEXANDER REUBEN MARKES MD
NPI 1164059523
Orthopaedic Surgery - Sports Medicine in San Francisco, CA

Active since March 25, 2020PECOS Enrolled
3838 CALIFORNIA ST RM 715, SAN FRANCISCO, CA 94118(415) 668-8010(415) 752-2560 Get Directions Write a Review

NPPES record last updated: September 28, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Sep 28, 2026, Apr 7, 2025, Mar 25, 2020 (3 updates tracked since 2020).

About Alexander Reuben Markes Md NPPES

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

ALEXANDER REUBEN MARKES MD (NPI 1164059523) is an individual sports medicine provider in San Francisco, California, licensed in California (A182896) and active in the NPI registry since March 2020. He is enrolled in Medicare PECOS and is a graduate of University Of California, San Francisco School Of Medicine (2020).

NPPES Registry Identity

NPI1164059523
Entity TypeIndividualMale
Primary Taxonomy207XX0005X
Provider Legal NameALEXANDER REUBEN MARKESCredential: MD
Location Address3838 CALIFORNIA ST RM 715San Francisco, CA 94118-1509
Mailing Address3838 California St Rm 715San Francisco, CA 94118-1509 · (415) 668-8010 · Fax (415) 752-2560
Phone(415) 668-8010
Fax(415) 752-2560
Sole ProprietorNo
Medical School CMSUniversity Of California, San Francisco School Of MedicineGraduated 2020
Enumeration DateMarch 25, 2020
Last NPPES UpdateSeptember 28, 20263 updates tracked since enumeration
NPPES CertifiedSeptember 28, 2026
✔ NPI 1164059523 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyOrthopaedic Surgery · Sports MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207XX0005X
License✔ Licensed in CA · A182896
Definition
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.
3838 CALIFORNIA ST RM 715, San Francisco, CA 94118
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Alexander Reuben Markes Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

PECOS PAC ID9931514486
PECOS Enrollment IDI20260701000912
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

2

Medicare enrollment records show Alexander Markes reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

California Pacific Orthopaedics And Sports Medicine A Medical Corporat
Same address
Orthopaedic Surgery
3838 CALIFORNIA ST., SUITE 715
San Francisco, CA 94118
  • Reassigned Medicare billing, California enrollment
  • 19 clinicians in this Medicare group
NPI 1093801524 (415) 592-2017
Regents Of The University Of California - Ucsf
1.6 mi
Multi-Specialty
505 PARNASSUS AVE
San Francisco, CA 94143
  • Reassigned Medicare billing, California enrollment
  • 82 clinicians in this Medicare group
NPI 1265890263 (415) 476-1000

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

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

JAMES DAMIAN KELLY II MD
Orthopaedic Surgery
3838 CALIFORNIA ST RM 715
SAN FRANCISCO, CA 94118
San Francisco County (415) 668-8010
MARK A. SCHRUMPF MD A PROFESSIONAL CORPORATION
Orthopaedic Surgery
3838 CALIFORNIA ST RM 715
SAN FRANCISCO, CA 94118
San Francisco County (415) 668-8010
DR. MARK ALAN SCHRUMPF M.D.
Orthopaedic Surgery
3838 CALIFORNIA ST RM 715
SAN FRANCISCO, CA 94118
San Francisco County (415) 668-8010
JOHNNA NICOLE WALKER PA-C
Physician Assistant (Surgical)
3838 CALIFORNIA ST RM 715
SAN FRANCISCO, CA 94118
San Francisco County (415) 668-8010
MR. JAMES ALFRED AICARDI PA-C
Physician Assistant (Surgical)
3838 CALIFORNIA ST RM 715
SAN FRANCISCO, CA 94118
San Francisco County (415) 668-8010
DR. KEITH WEI CHAN M.D.
Orthopaedic Surgery (Sports Medicine)
3838 CALIFORNIA ST RM 715
SAN FRANCISCO, CA 94118
San Francisco County (415) 668-8010
MR. MARCUS PADDOCK SCHWAB PA
Physician Assistant
3838 CALIFORNIA ST RM 715
SAN FRANCISCO, CA 94118
San Francisco County (415) 668-8010
SEYED ARSHAN ARSHAD DO
Orthopaedic Surgery
3838 CALIFORNIA ST RM 715
SAN FRANCISCO, CA 94118
San Francisco County (415) 668-8010

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 Alexander Markes's NPI number?

The NPI number for Alexander Markes is 1164059523. It was assigned to this individual provider in the NPPES registry on March 25, 2020.

Where is Alexander Markes located?

Alexander Markes practices at 3838 California St Rm 715, San Francisco, CA 94118. The listed phone number is (415) 668-8010.

What is Alexander Markes's specialty?

The primary specialty registered for this NPI is Orthopaedic Surgery, specializing in Sports Medicine, with taxonomy code 207XX0005X.

Is Alexander Markes enrolled in Medicare?

Yes. Alexander Markes is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Alexander Markes's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Alexander Markes reassigns Medicare benefits to 2 organizations: California Pacific Orthopaedics And Sports Medicine A Medical Corporat (San Francisco, CA) and Regents Of The University Of California - Ucsf (San Francisco, CA). Each 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 Alexander Markes's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Alexander Markes was last updated on September 28, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 34 days 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.