Sandisk insider activity
What the executives and directors of Sandisk actually did with their own shares, decoded from their SEC Form 4 filings. Each figure says the stretch of time it covers.
−$134M
net open-market flow, 12 m
0 open-market buys, 12 m
92.3%
of sale value on 10b5-1 plans, 12 m
– no insider buy on record
The tape: three years of insider trades
Open-market buy
Discretionary sale
Planned sale (10b5-1)
Reported-price path
Routine
Every marker sits at the price reported on the Form 4. The line is the monthly median of all prices insiders reported, so the chart needs no market feed; the grey strip is the routine flow (grants, vestings, tax withholding and gifts) that a headline gets wrong by counting it as selling.
The 99 routine events on the chart, as a list
| Date | Insider | Shares |
|---|---|---|
| Oct 20, 2026 | Shek Bernard | 322 |
| Sep 20, 2026 | Shek Bernard | 1,119 |
| Sep 17, 2026 | Goeckeler David | 3,296 |
| Sep 17, 2026 | Visoso Luis Felipe | 1,635 |
| Sep 17, 2026 | Pokorny Michael | 458 |
| Sep 17, 2026 | Ilkbahar Alper | 1,619 |
| Sep 3, 2026 | Goeckeler David | 11K |
| Sep 3, 2026 | Visoso Luis Felipe | 5,838 |
| Sep 3, 2026 | Pokorny Michael | 1,283 |
| Sep 3, 2026 | Ilkbahar Alper | 3,244 |
| Sep 3, 2026 | Shek Bernard | 2,271 |
| Aug 25, 2026 | Goeckeler David | 50K |
| Aug 25, 2026 | Ilkbahar Alper | 654 |
| Aug 25, 2026 | Shek Bernard | 212 |
| Aug 21, 2026 | Goeckeler David | 2,333 |
| Aug 21, 2026 | Visoso Luis Felipe | 27K |
| Aug 21, 2026 | Ilkbahar Alper | 1,035 |
| Aug 21, 2026 | Shek Bernard | 219 |
| Jun 20, 2026 | Shek Bernard | 117 |
| Jun 2, 2026 | Ilkbahar Alper | 2,694 |
| May 25, 2026 | Goeckeler David | 1,569 |
| May 25, 2026 | Ilkbahar Alper | 653 |
| May 25, 2026 | Shek Bernard | 211 |
| May 21, 2026 | Goeckeler David | 2,331 |
| May 21, 2026 | Ilkbahar Alper | 481 |
| May 21, 2026 | Shek Bernard | 216 |
| May 21, 2026 | Visoso Luis Felipe | 1,588 |
| May 12, 2026 | Caulfield Thomas | 9,666 |
| May 9, 2026 | Pokorny Michael | 1,429 |
| Apr 20, 2026 | Ilkbahar Alper | 2,251 |
| Apr 20, 2026 | Shek Bernard | 41 |
| Mar 20, 2026 | Shek Bernard | 117 |
| Mar 3, 2026 | Caulfield Thomas | 29K |
| Feb 25, 2026 | Goeckeler David | 1,569 |
| Feb 25, 2026 | Ilkbahar Alper | 566 |
| Feb 25, 2026 | Shek Bernard | 211 |
| Feb 21, 2026 | Goeckeler David | 2,332 |
| Feb 21, 2026 | Ilkbahar Alper | 345 |
| Feb 21, 2026 | Shek Bernard | 224 |
| Feb 21, 2026 | Visoso Luis Felipe | 1,594 |
| Jan 20, 2026 | Shek Bernard | 34 |
| Dec 30, 2025 | Bradley Alexander R. | 863 |
| Dec 20, 2025 | Shek Bernard | 117 |
| Nov 25, 2025 | Goeckeler David | 1,569 |
| Nov 25, 2025 | Ilkbahar Alper | 653 |
| Nov 25, 2025 | Shek Bernard | 211 |
| Nov 21, 2025 | Goeckeler David | 2,331 |
| Nov 21, 2025 | Ilkbahar Alper | 481 |
| Nov 21, 2025 | Shek Bernard | 216 |
| Nov 21, 2025 | Visoso Luis Felipe | 1,588 |
| Nov 20, 2025 | Pokorny Michael | 821 |
| Nov 18, 2025 | Suzuki Miyuki | 3,192 |
| Nov 18, 2025 | Sayiner Necip | 979 |
| Nov 18, 2025 | Caulfield Thomas | 979 |
| Nov 18, 2025 | KUMAR DEVINDER | 979 |
| Nov 18, 2025 | Shook Ellyn | 979 |
| Nov 18, 2025 | Cassidy Richard B. II | 1,143 |
| Oct 20, 2025 | Shek Bernard | 362 |
| Sep 20, 2025 | Shek Bernard | 117 |
| Sep 3, 2025 | Goeckeler David | 85K |
Where the shares went, last 12 months
Every Form 4 movement decomposed: what flowed in (grants, vested equity, purchases) and what flowed out (tax withholding, plan sales, discretionary sales, gifts). Counted in shares, because grants carry no price.
The chart, in numbers
| Flow | Shares |
|---|---|
| From holdings | 234K |
| Granted | 15K |
| Vested / exercised | 276 |
| Withheld for tax | 133K |
| Planned sales (10b5-1) | 80K |
| Discretionary sales | 9,796 |
| Gifts | 27K |
Skin in the game
Directly held shares as reported after each trade, indexed to 100 at the start of the window, up to five years back. Direct holdings only: trust and family-entity positions are per-entity in the filings and do not sum honestly, so this chart refuses to guess. The steps are the trades.
The chart, in numbers
| Insider | Start of the window | Latest reported | Indexed, start = 100 |
|---|---|---|---|
| WESTERN DIGITAL CORP | 145M | 7.5M | 5.2 |
| Goeckeler David | 486K | 395K | 81.2 |
| Visoso Luis Felipe | 155K | 133K | 85.7 |
| Ilkbahar Alper | 41K | 42K | 103.1 |
| Shek Bernard | 18K | 25K | 137.5 |
Who holds what
the 14 largest holdings of 15| Insider | Role | Shares held | Buys 12 m | Sales 12 m | 12 m | Last trade |
|---|---|---|---|---|---|---|
| WESTERN DIGITAL CORP | 10% owner | 7.5M | – | – | – | |
| Goeckeler David Chairman & CEO Last trade Sep 17, 2026 | CEO | 417K | – | $105M | net selling over the year: 0 months buying, 1 month selling | Sep 17, 2026 |
| Visoso Luis Felipe EVP & CFO Last trade Sep 15, 2026 | CFO | 133K | – | $1.6M | net selling over the year: 0 months buying, 1 month selling | Sep 15, 2026 |
| Ilkbahar Alper EVP & Chief Technology Officer Last trade Sep 3, 2026 | Officer | 42K | – | $11M | net selling over the year: 0 months buying, 2 months selling | Sep 3, 2026 |
| Shek Bernard Chief Legal Officer and Secty Last trade Nov 2, 2026 | Officer | 25K | – | $9.7M | net selling over the year: 0 months buying, 6 months selling | Nov 2, 2026 |
| Pokorny Michael VP, Chief Accounting Officer Last trade May 12, 2026 | Officer | 22K | – | $3.5M | net selling over the year: 0 months buying, 1 month selling | May 12, 2026 |
| Alexy Kimberly | Director | 14K | – | – | – | |
| Suzuki Miyuki Last trade Feb 25, 2026 | Director | 9,907 | – | $2.2M | net selling over the year: 0 months buying, 1 month selling | Feb 25, 2026 |
| Caulfield Thomas | Director | 7,146 | – | – | – | |
| Cassidy Richard B. II | Director | 4,914 | – | – | – | |
| MASSENGILL MATTHEW E | Director | 4,840 | – | – | – | |
| KUMAR DEVINDER | Director | 4,769 | – | – | – | |
| Shook Ellyn | Director | 4,750 | – | – | – | |
| Sayiner Necip Last trade May 8, 2026 | Director | 2,900 | – | $1.1M | net selling over the year: 0 months buying, 2 months selling | May 8, 2026 |
Open-market trade log
the 60 most recent of 77| Date | Insider | Type | Shares | Price | Value | Since trade | Filed |
|---|---|---|---|---|---|---|---|
| Nov 2, 2026 | Shek Bernard (Officer) 600 shares $1,158.26 +0.0% since trade filed Nov 3, 2026 | Planned sale (10b5-1) | 600 | $1,158.26 | $695K | +0.0% | Nov 3, 2026 |
| Oct 1, 2026 | Shek Bernard (Officer) 600 shares $1,734.94 −33.2% since trade filed Oct 2, 2026 | Planned sale (10b5-1) | 600 | $1,734.94 | $1.0M | −33.2% | Oct 2, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 40 shares $1,567.26 −26.1% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 40 | $1,567.26 | $63K | −26.1% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 165 shares $1,587.00 −27.0% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 165 | $1,587.00 | $262K | −27.0% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 306 shares $1,573.15 −26.4% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 306 | $1,573.15 | $481K | −26.4% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 640 shares $1,579.41 −26.7% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 640 | $1,579.41 | $1.0M | −26.7% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 910 shares $1,570.04 −26.2% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 910 | $1,570.04 | $1.4M | −26.2% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 1,080 shares $1,583.80 −26.9% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 1,080 | $1,583.80 | $1.7M | −26.9% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 1,157 shares $1,572.60 −26.4% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 1,157 | $1,572.60 | $1.8M | −26.4% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 1,480 shares $1,580.25 −26.7% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 1,480 | $1,580.25 | $2.3M | −26.7% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 1,520 shares $1,585.85 −27.0% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 1,520 | $1,585.85 | $2.4M | −27.0% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 2,588 shares $1,574.57 −26.4% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 2,588 | $1,574.57 | $4.1M | −26.4% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 2,778 shares $1,575.58 −26.5% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 2,778 | $1,575.58 | $4.4M | −26.5% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 2,876 shares $1,578.34 −26.6% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 2,876 | $1,578.34 | $4.5M | −26.6% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 4,139 shares $1,576.82 −26.5% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 4,139 | $1,576.82 | $6.5M | −26.5% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 4,558 shares $1,571.21 −26.3% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 4,558 | $1,571.21 | $7.2M | −26.3% | Sep 21, 2026 |
| Sep 17, 2026 | Goeckeler David (CEO) 9,604 shares $1,569.00 −26.2% since trade filed Sep 21, 2026 | Planned sale (10b5-1) | 9,604 | $1,569.00 | $15M | −26.2% | Sep 21, 2026 |
| Sep 15, 2026 | Visoso Luis Felipe (CFO) 1,000 shares $1,568.83 −26.2% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 1,000 | $1,568.83 | $1.6M | −26.2% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 181 shares $1,522.87 −23.9% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 181 | $1,522.87 | $276K | −23.9% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 359 shares $1,529.36 −24.3% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 359 | $1,529.36 | $549K | −24.3% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 360 shares $1,541.88 −24.9% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 360 | $1,541.88 | $555K | −24.9% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 700 shares $1,535.12 −24.6% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 700 | $1,535.12 | $1.1M | −24.6% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 864 shares $1,540.78 −24.8% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 864 | $1,540.78 | $1.3M | −24.8% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 1,200 shares $1,532.17 −24.4% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 1,200 | $1,532.17 | $1.8M | −24.4% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 1,480 shares $1,539.19 −24.8% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 1,480 | $1,539.19 | $2.3M | −24.8% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 1,695 shares $1,535.96 −24.6% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 1,695 | $1,535.96 | $2.6M | −24.6% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 2,280 shares $1,526.45 −24.1% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 2,280 | $1,526.45 | $3.5M | −24.1% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 3,075 shares $1,524.27 −24.0% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 3,075 | $1,524.27 | $4.7M | −24.0% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 3,200 shares $1,537.68 −24.7% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 3,200 | $1,537.68 | $4.9M | −24.7% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 4,080 shares $1,528.45 −24.2% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 4,080 | $1,528.45 | $6.2M | −24.2% | Sep 16, 2026 |
| Sep 14, 2026 | Goeckeler David (CEO) 14K shares $1,522.59 −23.9% since trade filed Sep 16, 2026 | Planned sale (10b5-1) | 14K | $1,522.59 | $22M | −23.9% | Sep 16, 2026 |
| Sep 8, 2026 | Shek Bernard (Officer) 2,308 shares $1,767.33 −34.5% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 2,308 | $1,767.33 | $4.1M | −34.5% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 40 shares $1,513.23 −23.5% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 40 | $1,513.23 | $61K | −23.5% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 40 shares $1,522.10 −23.9% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 40 | $1,522.10 | $61K | −23.9% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 40 shares $1,527.58 −24.2% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 40 | $1,527.58 | $61K | −24.2% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 40 shares $1,532.02 −24.4% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 40 | $1,532.02 | $61K | −24.4% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 40 shares $1,548.85 −25.2% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 40 | $1,548.85 | $62K | −25.2% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 40 shares $1,550.48 −25.3% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 40 | $1,550.48 | $62K | −25.3% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 40 shares $1,554.02 −25.5% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 40 | $1,554.02 | $62K | −25.5% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 40 shares $1,558.90 −25.7% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 40 | $1,558.90 | $62K | −25.7% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 40 shares $1,564.40 −26.0% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 40 | $1,564.40 | $63K | −26.0% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 40 shares $1,571.04 −26.3% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 40 | $1,571.04 | $63K | −26.3% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 52 shares $1,517.68 −23.7% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 52 | $1,517.68 | $79K | −23.7% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 68 shares $1,519.23 −23.8% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 68 | $1,519.23 | $103K | −23.8% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 78 shares $1,555.57 −25.5% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 78 | $1,555.57 | $121K | −25.5% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,515.05 −23.6% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,515.05 | $121K | −23.6% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,520.93 −23.9% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,520.93 | $122K | −23.9% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,523.61 −24.0% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,523.61 | $122K | −24.0% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,526.81 −24.1% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,526.81 | $122K | −24.1% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,529.71 −24.3% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,529.71 | $122K | −24.3% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,530.52 −24.3% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,530.52 | $122K | −24.3% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,534.48 −24.5% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,534.48 | $123K | −24.5% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,535.66 −24.6% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,535.66 | $123K | −24.6% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,538.41 −24.7% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,538.41 | $123K | −24.7% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,539.61 −24.8% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,539.61 | $123K | −24.8% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,541.01 −24.8% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,541.01 | $123K | −24.8% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,542.68 −24.9% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,542.68 | $123K | −24.9% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,546.02 −25.1% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,546.02 | $124K | −25.1% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,547.46 −25.2% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,547.46 | $124K | −25.2% | Sep 8, 2026 |
| Sep 3, 2026 | Ilkbahar Alper (Officer) 80 shares $1,557.79 −25.7% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 80 | $1,557.79 | $125K | −25.7% | Sep 8, 2026 |
“Since trade” compares with the latest insider-implied price, not a market quote: these pages are built from filings alone. A role here is the one on that day's Form 4, so somebody promoted since appears under both titles.
Filing hygiene
133 Forms 4, 3 years
0 filed late
1 amendments
1.7 avg. days to file
How to read this
A Form 4 transaction code decides everything. P is an open-market purchase and S an open-market sale; those two are the only codes where an insider chose to trade. A is a grant, M an option exercise or vesting, F shares withheld to cover tax, G a gift. Most “insiders dumped billions” headlines are code F and M mechanics.
Sales flagged 10b5-1 run on a plan the insider adopted in advance; since 2023 every Form 4 carries that flag. Buys have historically predicted returns, sales mostly have not, and this page states filings, not advice.