Mark Tony Williams, M.D.
Retina Specialist (Ophthalmology) Physician · Orange, CA
Mark Tony Williams, M.D. is a retina specialist (ophthalmology) physician with a practice address in Orange, California, and NPI 1780118802, issued on Apr 14, 2017. Check the license (California A187615, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Mark Tony Williams
- Credential
- M.D.
- Primary taxonomy
- Retina Specialist (Ophthalmology) Physician 207WX0107X
- License number
- A187615 CA
Self-reported in NPPES; status is on the state search - Practice location
- 1310 W Stewart Dr Ste 303, Orange, CA 92868
- Phone
- (714) 738-4621
- Enumerated
- Apr 14, 2017
- Record last updated
- Mar 11, 2025
- Fax
- (714) 409-0629
- Medicare enrollment
- Enrolled (PECOS I20230803003713); accepts Medicare assignment
- Medical or professional school
- University Of California, San Francisco School Of Medicine, 2017
- Entity
- Type 1 · individual
8 nearest retina specialist (ophthalmology) physician records → All 205 in California → Look up another NPI →
Verify Mark Tony Williams in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A187615Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
17% fewer Medicare Part D claims than the average retina specialist (ophthalmology) physician in 2024
513 Medicare Part D claims for 121 beneficiaries, against an average of 620 among the 1,449 providers of this specialty who prescribed in Part D. Brand-name drugs were 31% of claims.
Most prescribed
- Prednisolone Acetate117 claims
- Erythromycin82 claims
- Moxifloxacin76 claims
- Ketorolac Tromethamine49 claims
- Brimonidine Tartrate42 claims
- Atropine Sulfate39 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
The practice group's MIPS final score for 2023 (Medicare payment program): 93.3 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
Industry payments in 2024: $1,594.67
34 payments; by number, the most common kind was food and beverage; the largest payer was Regeneron Healthcare Solutions, Inc. The 1,253 providers of this specialty with any payment received $7,667.49 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through one group practice
- Southern California Permanente Medical GroupYorba Linda, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Mark Tony Williams among 205 retina specialist (ophthalmology) physician records in California
Mark Tony Williams, M.D. is one of 205 retina specialist (ophthalmology) physician records with a practice address in California. 98% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2017, is newer than 80% of them.
- NPI issued2017 · 80% of these records are older, 14% newer
- In a Medicare fileYes · 98% of these records are
- In the CMS Doctors and Clinicians fileYes · 92% of these records are
- Graduated2017 · median 2007 among the 189 with a school on file
- Record last updated2025 · 37% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207WX0107X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Retina Specialist (Ophthalmology) Physician providers in California
There are 205 retina specialist (ophthalmology) physician records in California.
All 205 in California → Every provider in Orange → Retina Specialist (Ophthalmology) Physician nationwide →
The 8 retina specialist (ophthalmology) physician records with the nearest ZIP codes
- Sean Adrean, M.D.Fullerton, CA 928351073566568
- Scott Grant, M.D.Fullerton, CA 928351194762310
- Ash Pirouz, MDFullerton, CA 928351942489356
- Hema Ramkumar, M.D.Fullerton, CA 928351184919524
- Saeed Javidi, MDSanta Ana, CA 927051487183364
- Esther Kim, MDSanta Ana, CA 927051649539404
- Desmond McGuire, MDSanta Ana, CA 927051881690634
- Robert See, M.D.Oxnard, CA 930361407955073
Common questions
What is Mark Tony Williams, M.D.'s NPI number?
Mark Tony Williams, M.D.'s National Provider Identifier (NPI) is 1780118802, issued on Apr 14, 2017. An NPI identifies a provider in billing; it is not a license.
Where is Mark Tony Williams, M.D. located?
The NPPES record lists a practice address at 1310 W Stewart Dr Ste 303, Orange, CA, 92868. Phone: (714) 738-4621. Providers update this record themselves, so call before visiting.
How can I verify Mark Tony Williams, M.D.'s license?
NPPES lists California license number A187615, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Mark Tony Williams, M.D. prescribe under Medicare Part D?
In 2024, Mark Tony Williams, M.D. had 513 Medicare Part D claims for 121 beneficiaries; the average among retina specialist (ophthalmology) physician prescribers was 620. Part D covers Medicare prescriptions only.
What is Mark Tony Williams, M.D.'s MIPS final score?
The 2023 MIPS final score is 93.3 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.