WESTERN DIGITAL CORP WDC
COM · Common Stock · CUSIP 958102105 · ISIN US9581021055
American computer storage corporation
- SectorTechnology
- IndustryComputer Storage Devices
- HeadquartersSan Jose, CA
- Founded1970
- Websitewesterndigital.com
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($793.3m this quarter). Holder counts are more reliable. Shares outstanding: 360.5m as of 2026-08-07, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $637.95. Options: 67 managers hold calls ($8.9bn notional), 56 hold puts ($23.5bn).
Trends to Q2 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 578 |
| Q4 2022 | 528 |
| Q1 2023 | 539 |
| Q2 2023 | 538 |
| Q3 2023 | 544 |
| Q4 2023 | 610 |
| Q1 2024 | 684 |
| Q2 2024 | 759 |
| Q3 2024 | 699 |
| Q4 2024 | 713 |
| Q1 2025 | 666 |
| Q2 2025 | 751 |
| Q3 2025 | 961 |
| Q4 2025 | 1,173 |
| Q1 2026 | 1,420 |
| Q2 2026 | 1,846 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q3 2024 | 340 | 420 |
| Q4 2024 | 342 | 317 |
| Q1 2025 | 359 | 340 |
| Q2 2025 | 451 | 293 |
| Q3 2025 | 629 | 300 |
| Q4 2025 | 643 | 433 |
| Q1 2026 | 779 | 592 |
| Q2 2026 | 1,105 | 687 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q3 2025 | $2.4bn | $3.2bn | 1.34 |
| Q4 2025 | $3.0bn | $5.2bn | 1.76 |
| Q1 2026 | $3.3bn | $7.0bn | 2.13 |
| Q2 2026 | $8.9bn | $23.5bn | 2.65 |
Biggest buyers
| Capital World Investors | Added | +4.7m |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | Added | +1.8m |
| Capital International Investors | New | +1.8m |
| Invesco Ltd. | Added | +1.8m |
| EXCHANGE TRADED CONCEPTS, LLC | Added | +1.7m |
| JANE STREET GROUP, LLC | Added | +1.0m |
| Qube Research & Technologies Ltd | New | +915.9k |
| Nuveen, LLC | Added | +859.9k |
| WELLINGTON MANAGEMENT GROUP LLP | Added | +830.2k |
| STATE STREET CORP | Added | +810.8k |
Biggest sellers
| FMR LLC | Reduced | -5.6m |
| WCM INVESTMENT MANAGEMENT, LLC | Reduced | -4.9m |
| VANGUARD PORTFOLIO MANAGEMENT LLC | Reduced | -4.1m |
| UBS Group AG | Reduced | -2.9m |
| BlackRock, Inc. | Reduced | -2.8m |
| AMERIPRISE FINANCIAL INC | Reduced | -2.4m |
| BANK OF AMERICA CORP /DE/ | Reduced | -2.0m |
| Amundi | Reduced | -1.2m |
| Soroban Capital Partners LP | Sold out | -1.1m |
| GEODE CAPITAL MANAGEMENT, LLC | Reduced | -1.1m |
Biggest calls
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $2.8bn4.5m shares |
| CITADEL ADVISORS LLC | Added | $1.5bn2.3m shares |
| JANE STREET GROUP, LLC | Added | $1.4bn2.2m shares |
| IMC-Chicago, LLC | Added | $903.8m1.4m shares |
| GOLDMAN SACHS GROUP INC | Added | $294.8m461.6k shares |
| Walleye Trading LLC | Reduced | $256.8m402.1k shares |
| UBS Group AG | Reduced | $215.7m337.7k shares |
| MILLENNIUM MANAGEMENT LLC | Added | $199.0m311.6k shares |
| GROUP ONE TRADING LLC | Reduced | $171.0m267.7k shares |
| SIMPLEX TRADING, LLC | Reduced | $129.9m201.6k shares |
Biggest puts
| JANE STREET GROUP, LLC | Added | $6.1bn9.6m shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $4.0bn6.3m shares |
| CITADEL ADVISORS LLC | Added | $3.7bn5.8m shares |
| WELLS FARGO & COMPANY/MN | Reduced | $2.6bn4.0m shares |
| IMC-Chicago, LLC | Added | $1.3bn2.1m shares |
| BNP PARIBAS FINANCIAL MARKETS | Added | $867.4m13.6k shares |
| Caption Management, LLC | Added | $636.2m996.0k shares |
| Walleye Trading LLC | Reduced | $507.2m794.1k shares |
| D. E. Shaw & Co., Inc. | Reduced | $500.9m784.2k shares |
| GOLDMAN SACHS GROUP INC | Added | $491.1m768.9k shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| VANGUARD CAPITAL MANAGEMENT LLC 13G · institution new · filed 2026-04-30 | 7.5% |
| FMR LLC 13G · institution -2.9 pts · filed 2026-08-06 | 7.2% |
| JPMORGAN CHASE & CO 13G · institution -1.4 pts · filed 2025-04-22 | 5.3% |
Fell to 5% or below in the last year: VANGUARD PORTFOLIO MANAGEMENT LLC (3.6%, 2026-07-31; now reported by VANGUARD CAPITAL MANAGEMENT LLC), VANGUARD GROUP INC (0.0%, 2026-03-27; now reported by VANGUARD CAPITAL MANAGEMENT LLC), MANAGED ACCOUNT ADVISORS LLC (2.6%, 2026-02-10)
Insider purchases and sales since 1 Apr 2026
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q4 2024 | 0 | — | 3 | $7.8m | $5.5m |
| Q1 2025 | 0 | — | 1 | $88.4k | $88.4k |
| Q2 2025 | 0 | — | 2 | $657.5k | $657.5k |
| Q3 2025 | 0 | — | 4 | $3.9m | $2.2m |
| Q4 2025 | 0 | — | 6 | $10.6m | $5.6m |
| Q1 2026 | 0 | — | 6 | $28.7m | $21.9m |
| Q2 2026 | 0 | — | 6 | $19.8m | $16.0m |
| Q3 2026 | 0 | — | 5 | $15.8m | $12.4m |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2026-09-04 | Gubbi Vidyadhara K Chief of Global Operations | Sold | $825.5k1.8k shares |
| 2026-09-04 | Tregillis Cynthia L Chief Legal Officer & Corp Sec | Sold plan | $194.9k432 shares |
| 2026-09-01 | STREETER STEPHANIE A Director · By Family Trust | Sold | $728.0k1.6k shares |
| 2026-08-31 | STREETER STEPHANIE A Director · By Family Trust | Sold | $1.8m4.0k shares |
| 2026-08-27 | Tregillis Cynthia L Chief Legal Officer & Corp Sec | Sold plan | $481.7k1.0k shares |
| 2026-08-26 | Tregillis Cynthia L Chief Legal Officer & Corp Sec | Sold plan | $214.6k476 shares |
| 2026-08-24 | Tregillis Cynthia L Chief Legal Officer & Corp Sec | Sold plan | $305.2k684 shares |
| 2026-08-21 | Tregillis Cynthia L Chief Legal Officer & Corp Sec | Sold plan | $112.2k235 shares |
| 2026-08-11 | Tan Irving Chief Executive Officer, director | Sold plan | $8.9m20.0k shares |
| 2026-07-28 | Cole Martin I Director | Sold plan | $1.7m3.8k shares |
| 2026-07-28 | Cole Martin I Director | Sold plan | $88.9k192 shares |
| 2026-07-21 | Tregillis Cynthia L Chief Legal Officer & Corp Sec | Sold plan | $427.9k808 shares |
| 2026-06-09 | Cole Martin I Director | Sold plan | $1.7m3.3k shares |
| 2026-06-09 | Cole Martin I Director | Sold plan | $385.9k720 shares |
| 2026-06-05 | Tregillis Cynthia L Chief Legal Officer & Corp Sec | Sold plan | $235.7k432 shares |
| 2026-06-01 | Gubbi Vidyadhara K Chief of Global Operations | Sold | $1.4m2.5k shares |
| 2026-05-28 | KIDDOO BRUCE E Director | Sold | $396.4k750 shares |
| 2026-05-27 | Tregillis Cynthia L Chief Legal Officer & Corp Sec | Sold plan | $115.5k214 shares |
| 2026-05-22 | Tregillis Cynthia L Chief Legal Officer & Corp Sec | Sold plan | $150.5k308 shares |
| 2026-05-21 | Tregillis Cynthia L Chief Legal Officer & Corp Sec | Sold plan | $48.6k106 shares |
| 2026-05-11 | Davis Brian Scott Chief Sales & Mrktng Officer | Sold plan | $5.0m10.0k shares |
| 2026-05-04 | Gubbi Vidyadhara K Chief of Global Operations | Sold | $2.1m4.7k shares |
| 2026-05-01 | Tan Irving Chief Executive Officer, director | Sold plan | $8.2m20.0k shares |
| 2026-04-21 | Tregillis Cynthia L Chief Legal Officer & Corp Sec | Sold plan | $136.9k363 shares |
Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).
Holders, Q2 2026
| Manager | Shares | Change |
|---|---|---|
| BlackRock, Inc. 0.31% of their portfolio | 33.0m $21.0bn | Reduced -2.8m |
| FMR LLC 0.72% of their portfolio | 26.0m $16.6bn | Reduced -5.6m |
| VANGUARD CAPITAL MANAGEMENT LLC 0.31% of their portfolio | 22.5m $14.4bn | Added +475.9k |
| JPMORGAN CHASE & CO 0.65% of their portfolio | 17.0m $11.1bn | Reduced -504.4k |
| Capital World Investors 1.25% of their portfolio | 16.6m $10.6bn | Added +4.7m |
| STATE STREET CORP 0.31% of their portfolio | 16.3m $10.4bn | Added +810.8k |
| Invesco Ltd. 0.73% of their portfolio | 14.4m $9.2bn | Added +1.8m |
| VANGUARD PORTFOLIO MANAGEMENT LLC 0.38% of their portfolio | 13.1m $8.4bn | Reduced -4.1m |
| GEODE CAPITAL MANAGEMENT, LLC 0.29% of their portfolio | 8.4m $5.4bn | Reduced -1.1m |
| MORGAN STANLEY 0.28% of their portfolio | 8.1m $5.2bn | Added +209.0k |
| BANK OF AMERICA CORP /DE/ 0.27% of their portfolio | 6.5m $4.1bn | Reduced -2.0m |
| GOLDMAN SACHS GROUP INC 0.35% of their portfolio | 5.2m $3.3bn | Reduced -227.9k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.55% of their portfolio | 4.7m $3.0bn | Added +1.8m |
| NORGES BANK 0.29% of their portfolio | 4.6m $3.0bn | Not comparable |
| Nuveen, LLC 0.58% of their portfolio | 3.8m $2.4bn | Added +859.9k |
| NORTHERN TRUST CORP 0.27% of their portfolio | 3.7m $2.3bn | Added +56.8k |
| AMERIPRISE FINANCIAL INC 0.44% of their portfolio | 3.4m $2.2bn | Reduced -2.4m |
| AQR CAPITAL MANAGEMENT LLC 0.65% of their portfolio | 2.9m $1.9bn | Reduced -518.6k |
| Bank of New York Mellon Corp 0.31% of their portfolio | 2.9m $1.9bn | Added +408.1k |
| Capital Research Global Investors 0.25% of their portfolio | 2.8m $1.8bn | Reduced -493.1k |
| Legal & General Group Plc 0.33% of their portfolio | 2.5m $1.6bn | Added +380.4k |
| DIMENSIONAL FUND ADVISORS LP 0.28% of their portfolio | 2.4m $1.6bn | Reduced -55.2k |
| FRED ALGER MANAGEMENT, LLC 4.70% of their portfolio | 2.2m $1.4bn | Reduced -453.5k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.18% of their portfolio | 2.1m $1.4bn | Reduced -74.5k |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.13% of their portfolio | 2.1m $1.3bn | Reduced -570.7k |
| VANGUARD FIDUCIARY TRUST CO 0.28% of their portfolio | 2.0m $1.3bn | Added +70.8k |
| D. E. Shaw & Co., Inc. 0.75% of their portfolio | 1.9m $1.2bn | Reduced -786.4k |
| Amundi 0.28% of their portfolio | 1.8m $1.2bn | Reduced -1.2m |
| Capital International Investors 0.24% of their portfolio | 1.8m $1.2bn | New |
| EXCHANGE TRADED CONCEPTS, LLC 5.65% of their portfolio | 1.8m $1.1bn | Added +1.7m |
| BANK OF MONTREAL /CAN/ 0.38% of their portfolio | 1.6m $1.0bn | Added +229.6k |
| WCM INVESTMENT MANAGEMENT, LLC 1.93% of their portfolio | 1.6m $1.1bn | Reduced -4.9m |
| BNP PARIBAS FINANCIAL MARKETS 0.50% of their portfolio | 1.5m $954.0m | Added +304.6k |
| Anther Capital Ltd 23.09% of their portfolio | 1.4m $901.6m | Added +699.2k |
| DEUTSCHE BANK AG\ 0.26% of their portfolio | 1.4m $885.6m | Reduced -486.3k |
| National Pension Service 0.57% of their portfolio | 1.4m $882.0m | Reduced -57.1k |
| Maple Rock Capital Partners Inc. 17.01% of their portfolio | 1.4m $867.3m | Reduced -42.6k |
| ROYAL BANK OF CANADA 0.14% of their portfolio | 1.3m $838.0m | Added +41.0k |
| UBS Group AG 0.13% of their portfolio | 1.3m $803.8m | Reduced -2.9m |
| HSBC HOLDINGS PLC 0.36% of their portfolio | 1.2m $752.8m | Reduced -366.4k |
| JANE STREET GROUP, LLC 0.43% of their portfolio | 1.1m $672.1m | Added +1.0m |
| CITIGROUP INC 0.30% of their portfolio | 1.0m $643.2m | Added +434.5k |
| Value Aligned Research Advisors, LLC 3.77% of their portfolio | 988.4k $631.3m | Reduced -307.0k |
| Trivest Advisors Ltd 19.73% of their portfolio | 982.6k $627.6m | Added +637.6k |
| Swiss National Bank 0.33% of their portfolio | 976.0k $623.4m | Reduced -27.3k |
| Qube Research & Technologies Ltd 0.65% of their portfolio | 915.9k $585.0m | New |
| NATIONAL BANK OF CANADA /FI/ 0.51% of their portfolio | 909.5k $581.0m | Added +474.8k |
| Castle Hook Partners LP 6.18% of their portfolio | 903.4k $577.0m | Added +24.4k |
| Mitsubishi UFJ Asset Management Co., Ltd. 0.31% of their portfolio | 875.6k $559.3m | Added +78.6k |
| WELLS FARGO & COMPANY/MN 0.10% of their portfolio | 863.4k $551.5m | Reduced -161.1k |
| WELLINGTON MANAGEMENT GROUP LLP 0.10% of their portfolio | 863.2k $551.3m | Added +830.2k |
| Sumitomo Mitsui Trust Group, Inc. 0.31% of their portfolio | 855.1k $546.2m | Added +18.5k |
| AMF Tjanstepension AB 3.22% of their portfolio | 850.8k $543.5m | Reduced -523.1k |
| BARCLAYS PLC 0.17% of their portfolio | 832.6k $531.8m | Reduced -217.4k |
| Clear Street Group Inc. 1.65% of their portfolio | 817.9k $522.4m | Added +577.1k |
| Polar Capital Holdings Plc 1.44% of their portfolio | 793.3k $506.7m | Reduced -179.2k |
| WT Asset Management Ltd 9.91% of their portfolio | 784.2k $500.9m | Reduced -32.5k |
| BANK OF NOVA SCOTIA 0.76% of their portfolio | 783.2k $500.3m | Added +420.0k |
| California Public Employees Retirement System 0.28% of their portfolio | 767.8k $490.4m | Added +96.1k |
| NOMURA ASSET MANAGEMENT INTERNATIONAL INC. 0.72% of their portfolio | 748.6k $478.1m | Reduced -143.1k |
| Vanguard Global Advisers, LLC 0.22% of their portfolio | 747.0k $477.1m | Added +1.8k |
| FIRST TRUST ADVISORS LP 0.28% of their portfolio | 738.2k $471.5m | Added +368.3k |
| FRANKLIN RESOURCES INC 0.10% of their portfolio | 715.3k $456.9m | Added +432.7k |
| PRINCIPAL FINANCIAL GROUP INC 0.21% of their portfolio | 685.2k $437.7m | Added +9.2k |
| VANGUARD ASSET MANAGEMENT, Ltd 0.29% of their portfolio | 663.4k $423.7m | Added +75.0k |
| CITADEL ADVISORS LLC 0.24% of their portfolio | 657.9k $420.2m | Added +392.0k |
| Jericho Capital Asset Management L.P. 3.40% of their portfolio | 644.8k $411.8m | Added +63.2k |
| RHUMBLINE ADVISERS 0.31% of their portfolio | 633.2k $404.4m | Added +38.8k |
| Robeco Institutional Asset Management B.V. 0.49% of their portfolio | 630.7k $402.8m | Reduced -354.0k |
| NEUBERGER BERMAN GROUP LLC 0.26% of their portfolio | 621.5k $397.0m | Added +165.2k |
| ALLIANCEBERNSTEIN L.P. 0.05% of their portfolio | 587.8k $159.0m | Reduced -175.3k |
| RENAISSANCE TECHNOLOGIES LLC 0.47% of their portfolio | 537.5k $343.3m | Reduced -608.7k |
| ACADIAN ASSET MANAGEMENT LLC 0.40% of their portfolio | 532.6k $340.1m | Reduced -97.3k |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.31% of their portfolio | 529.8k $338.4m | Added +5.4k |
| Clal Insurance Enterprises Holdings Ltd 1.50% of their portfolio | 523.2k $334.2m | Reduced -125.0k |
| PRIMECAP MANAGEMENT CO/CA/ 0.20% of their portfolio | 516.4k $329.9m | Reduced -60.8k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.29% of their portfolio | 515.7k $329.4m | Reduced -53.1k |
| DZ BANK AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main 0.25% of their portfolio | 492.0k $314.2m | Reduced -335.7k |
| LPL Financial LLC 0.07% of their portfolio | 482.3k $308.0m | Added +85.4k |
| NORDEA INVESTMENT MANAGEMENT AB 0.24% of their portfolio | 455.4k $295.3m | Added +75.0k |
| ENVESTNET ASSET MANAGEMENT INC 0.07% of their portfolio | 440.9k $281.6m | Reduced -260.5k |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. 0.28% of their portfolio | 434.7k $277.9m | Added +61.1k |
| CANADA PENSION PLAN INVESTMENT BOARD 0.15% of their portfolio | 425.2k $271.6m | Added +91.2k |
| HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND 0.38% of their portfolio | 419.6k $268.0m | Added +126.4k |
| SEI INVESTMENTS CO 0.23% of their portfolio | 410.4k $262.1m | Reduced -84.7k |
| PRUDENTIAL FINANCIAL INC 0.28% of their portfolio | 409.0k $261.2m | Reduced -207.7k |
| Whale Rock Capital Management LLC 2.05% of their portfolio | 400.7k $255.9m | Reduced -11.3k |
| MARSHALL WACE, LLP 0.22% of their portfolio | 400.3k $255.7m | Reduced -531.0k |
| ProShare Advisors LLC 0.37% of their portfolio | 395.3k $252.5m | Reduced -106.0k |
| Universal- Beteiligungs- und Servicegesellschaft mbH 0.38% of their portfolio | 394.0k $250.3m | Reduced -79.9k |
| ASSETMARK, INC 0.40% of their portfolio | 364.9k $233.1m | Added +125.9k |
| VOYA INVESTMENT MANAGEMENT LLC 0.20% of their portfolio | 364.0k $232.5m | Reduced -453.6k |
| VICTORY CAPITAL MANAGEMENT INC 0.13% of their portfolio | 357.1k $228.1m | Reduced -139.9k |
| NOMURA ASSET MANAGEMENT CO LTD 0.49% of their portfolio | 356.8k $227.9m | Reduced -152.4k |
| MILLENNIUM MANAGEMENT LLC 0.15% of their portfolio | 352.0k $224.8m | Added +74.3k |
| NEW YORK STATE COMMON RETIREMENT FUND 0.28% of their portfolio | 349.0k $222.9m | Added +160.1k |
| Russell Investments Group, Ltd. 0.20% of their portfolio | 348.7k $223.4m | Reduced -53.0k |
| Pictet Asset Management Holding SA 0.21% of their portfolio | 348.4k $222.6m | Added +132.7k |
| NATIXIS ADVISORS, LLC 0.24% of their portfolio | 330.9k $211.4m | Reduced -93.0k |
| Bahl & Gaynor LLC 0.95% of their portfolio | 321.2k $205.1m | Reduced -4.2k |