William J Marks, MD
Neurology · Stanford
- Medicare standing
- Clear
- Enrolled, allowed to bill and order, not excluded
- Plans that list them
- 17
- 3 carriers
- Office
- 1
Offices
1 location · Stanford Health Care · 3,152 clinicians in this group
Plans that list them
17 plans · 3 carriers
A missing listing does not mean out of network. Directories change, and a listing does not cover every office. Call Dr. Marks’s office at (650) 723-4000 to confirm they take your plan. Ask about the office you use, its medical group, referrals and appointments.
17 of 17 plans
| Alignment Health BreathEasy (HMO C-SNP) | Alignment Health Plan | Listed | Oct 3, 2026 |
| Alignment Health Clarity (HMO C-SNP) | Alignment Health Plan | Listed | Oct 3, 2026 |
| Alignment Health Harmony (HMO) | Alignment Health Plan | Listed | Oct 3, 2026 |
| Alignment Health Heart & Diabetes (HMO C-SNP) | Alignment Health Plan | Listed | Oct 3, 2026 |
| Alignment Health Heart & Diabetes CalPlus (HMO C-SNP) | Alignment Health Plan | Listed | Oct 3, 2026 |
| Alignment Health Heart & Diabetes Care (HMO C-SNP) | Alignment Health Plan | Listed | Sep 28, 2026 |
| Alignment Health Heart & Diabetes Choice (HMO C-SNP) | Alignment Health Plan | Listed | Sep 28, 2026 |
| Alignment Health Honor+ Plan (HMO) | Alignment Health Plan | Listed | Oct 3, 2026 |
| Alignment Health My Choice CalCare (HMO) | Alignment Health Plan | Listed | Oct 3, 2026 |
| Alignment Health Silicon (HMO C-SNP) | Alignment Health Plan | Listed | Oct 3, 2026 |
| Alignment Health smartHMO (HMO) | Alignment Health Plan | Listed | Oct 3, 2026 |
| Alignment Health the ONE (HMO) | Alignment Health Plan | Listed | Oct 3, 2026 |
| SCAN Balance (HMO C-SNP) | SCAN Health Plan | Listed | Oct 3, 2026 |
| SCAN Classic (HMO) | SCAN Health Plan | Listed | Oct 3, 2026 |
| SCAN MyChoice (HMO) | SCAN Health Plan | Listed | Oct 3, 2026 |
| SCAN Strive (HMO C-SNP) | SCAN Health Plan | Listed | Oct 3, 2026 |
| DualConnect (HMO D-SNP) | Santa Clara Family Health Plan | Listed | Sep 1, 2026 |
California Medical Board record
Licence A51191 · Current
Licensed to practise in California · since 1992 · expires 2028-03-31 · Johns Hopkins University School of Medicine.
No disciplinary actions, convictions, malpractice judgments or citations in this record.
Original Medicare doctor bills
$1,684
Medicare paid this office $1,684 for 11 people.
This is what Medicare paid the clinician — not Medicare Advantage, and not the pharmacy.
Who their Medicare patients are
11 Original Medicare patients in 2024. Average age 74 · Health risk score 1.52. At or below the middle of the specialty; the typical neurology clinician is at 1.61.
The office billed $4,370, Medicare allowed $2,186 and paid $1,684; for 21 services of 4 kinds.
Original Medicare patients only. A risk score of 1.0 is the average Medicare patient; higher means sicker. Any count under 11 is hidden.
Year by year
| 2024 | 11 | 21 | 74 | 1.52 | $4,370 | $1,684 |
| 2022 | 16 | 56 | 75 | 1.13 | $8,894 | $3,329 |
| 2021 | 13 | 47 | 73 | 1.94 | $7,713 | $2,487 |
| 2020 | 15 | 44 | 74 | 1.23 | $9,765 | $2,402 |
| 2019 | 15 | 43 | 75 | 1.39 | $4,960 | $1,546 |
| 2018 | 18 | 43 | 73 | 1.23 | $10,414 | $3,052 |
| 2017 | 13 | 37 | 72 | 1.28 | $8,798 | $2,691 |
| 2015 | 14 | 23 | 74 | 1.67 | $14,666 | $1,843 |
| 2014 | 22 | 40 | 67 | 1.12 | $26,015 | $3,374 |
Original Medicare only. A service billed for fewer than 11 people in a year is hidden, so the lines can add up to less than the year's total.
See the services billed each year
2019: 1 service
| Short return visit | 12 | $324 | $19 |
Drugs they prescribed that Part D paid
$17,183
Pharmacies billed $17,183 in 2024.
This is pharmacy cost, not the office bill, and not what patients paid.
Opioids were 0% of their Part D prescriptions (0 of 99) in 2024. At or below the middle of the specialty; the typical neurology clinician is at 0%.
90 generic and fewer than 11 brand-name prescriptions · $17,183 in drug cost.
Part D prescriptions only. The opioid rate is opioid prescriptions as a share of all this clinician's Part D prescriptions; surgeons and pain specialists run higher than others, so it is shown against the same specialty.
| Carbidopa-Levodopa Er | 27 | $1,692 | $63 |
| Carbidopa-Levodopa | 35 | $1,612 | $46 |
| Pramipexole Er | 11 | $1,103 | $100 |
| Clonazepam | 12 | $121 | $10 |
Year by year
| 2024 | 99 | 15 | 0% (0) | None | $17,183 |
| 2023 | 100 | 15 | 0% (0) | 14% | $41,511 |
| 2022 | 88 | 17 | 0% (0) | 14% | $39,517 |
| 2021 | 57 | 16 | 0% (0) | None | $7,592 |
| 2020 | 66 | 17 | 0% (0) | 0% | $11,816 |
| 2019 | 96 | 14 | 0% (0) | None | $33,789 |
| 2018 | 55 | 12 | 0% (0) | None | $20,728 |
| 2017 | 47 | None | 0% (0) | None | $19,527 |
| 2016 | 30 | None | 0% (0) | 40% | $21,662 |
| 2015 | 25 | None | 0% (0) | 44% | $14,860 |
| 2014 | 15 | None | 0% (0) | None | $3,616 |
| 2013 | 35 | None | 0% (0) | None | $10,295 |
Part D prescriptions only. A drug prescribed to fewer than 11 people in a year is hidden.
See the drugs prescribed each year
2023: 3 drugs
| Carbidopa-Levodopa | 27 | $3,460 | $128 |
| Carbidopa-Levodopa Er | 36 | $2,507 | $70 |
| Clonazepam | 12 | $22 | $2 |
2022: 2 drugs
| Carbidopa-Levodopa | 31 | $3,836 | $124 |
| Carbidopa-Levodopa Er | 27 | $2,083 | $77 |
2021: 2 drugs
| Carbidopa-Levodopa Er | 23 | $3,208 | $139 |
| Carbidopa-Levodopa | 18 | $1,589 | $88 |
2020: 2 drugs
| Carbidopa-Levodopa Er | 27 | $3,053 | $113 |
| Carbidopa-Levodopa | 31 | $2,195 | $71 |
2019: 3 drugs
| Carbidopa | 16 | $19,360 | $1,210 |
| Carbidopa-Levodopa Er | 29 | $2,978 | $103 |
| Carbidopa-Levodopa | 37 | $2,761 | $75 |
2018: 2 drugs
| Carbidopa-Levodopa | 19 | $2,047 | $108 |
| Carbidopa-Levodopa Er | 16 | $1,171 | $73 |
2017: 2 drugs
| Carbidopa-Levodopa | 22 | $1,411 | $64 |
| Carbidopa-Levodopa Er | 12 | $890 | $74 |
2013: 1 drug
| Carbidopa-Levodopa | 11 | $1,920 | $175 |
Money from drug and device companies
$26 in 2025
| 2025 | 1 | 1 | None | $26 |
| 2024 | 1 | 1 | None | $149 |
| 2019 | 2 | 3 | None | $173 |
Paid work is consulting, speaking, honoraria and royalties, as opposed to meals and travel.
A payment is not proof that care is biased.
| InSightec | Exablate | $26 | 1 payment
|
See the published payment
| InSightec | Meals · 2025-04-07 | Exablate | $26 |
See earlier years (2024, 2019)
2024: $149
| InSightec | Exablate | $149 | 1 payment
|
2019: $173
| Eli Lilly and | None | $89 | 1 payment
|
| Boston Scientific | Vercise | $84 | 2 payments
|
Checkups this office reported
Medicare did not publish checkup rates for this clinician.
- Medicare’s overall office score
- 76.5 / 100
- Scores the office’s reporting and systems. It is not a grade for how the doctor treats you.
Professional record
- NPI
- 1053341693
- Licence
- CA A51191California A51191: Current · expires 2028-03-31
- Trained
- Johns Hopkins University School of Medicine, 1991
- Group
- Stanford Health Care
- Gender
- Male
More record details
- Sole proprietor
- No
- Medicaid ID
- CA 00A511910
- Taxonomy
- Neurology (2084N0400X); Federal specialty code 2084E0001X (2084E0001X); Federal specialty code 2084N0600X (2084N0600X)
- Mailing address
- 300 Pasteur Dr, Stanford, CA, 94305
- NPI first listed
- 2006-07-03
- NPI last updated
- 2023-11-08
- NPI record certified
- 2023-11-08
This is when the NPI record was last certified, not a medical board exam.