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 ($51.3m this quarter). Holder counts are more reliable. Shares outstanding: 346.9m as of 2025-07-23, 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 ≈ $63.98. Options: 46 managers hold calls ($1.0bn notional), 49 hold puts ($940.9m).
Trends to Q2 2025
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 |
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 2023 | 228 | 277 |
| Q4 2023 | 287 | 244 |
| Q1 2024 | 381 | 266 |
| Q2 2024 | 426 | 281 |
| Q3 2024 | 340 | 420 |
| Q4 2024 | 342 | 317 |
| Q1 2025 | 359 | 340 |
| Q2 2025 | 451 | 293 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q3 2024 | $1.7bn | $1.0bn | 0.59 |
| Q4 2024 | $1.5bn | $837.2m | 0.54 |
| Q1 2025 | $954.2m | $436.6m | 0.46 |
| Q2 2025 | $1.0bn | $940.9m | 0.92 |
Biggest buyers
| BANK OF AMERICA CORP /DE/ | Added | +7.6m |
| BlackRock, Inc. | Added | +4.9m |
| FMR LLC | Added | +4.7m |
| ROYAL BANK OF CANADA | Added | +3.2m |
| Soroban Capital Partners LP | Added | +2.9m |
| Impactive Capital LP | Added | +2.9m |
| D. E. Shaw & Co., Inc. | Added | +2.9m |
| FIL Ltd | Added | +2.9m |
| GOLDMAN SACHS GROUP INC | Added | +2.8m |
| Balyasny Asset Management L.P. | Added | +1.7m |
Biggest sellers
| JPMORGAN CHASE & CO | Reduced | -8.6m |
| UBS Group AG | Reduced | -5.7m |
| Alyeska Investment Group, L.P. | Reduced | -4.1m |
| PRICE T ROWE ASSOCIATES INC /MD/ | Reduced | -2.0m |
| Sachem Head Capital Management LP | Sold out | -1.8m |
| Slate Path Capital LP | Reduced | -1.6m |
| NORGES BANK | Reduced | -1.6m |
| Amundi | Reduced | -1.3m |
| Squarepoint Ops LLC | Reduced | -1.3m |
| CANADA PENSION PLAN INVESTMENT BOARD | Reduced | -1.2m |
Biggest calls
| CITADEL ADVISORS LLC | Reduced | $223.6m3.5m shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $163.4m2.6m shares |
| PEAK6 LLC | Added | $146.9m2.3m shares |
| JANE STREET GROUP, LLC | Reduced | $72.7m1.1m shares |
| Walleye Trading LLC | Reduced | $52.8m1.3m shares |
| IMC-Chicago, LLC | Reduced | $38.3m598.0k shares |
| Balyasny Asset Management L.P. | Added | $31.1m485.4k shares |
| Rokos Capital Management LLP | New | $29.1m455.0k shares |
| SIMPLEX TRADING, LLC | Reduced | $26.2m490.1k shares |
| Qube Research & Technologies Ltd | Added | $24.7m386.4k shares |
Biggest puts
| CITADEL ADVISORS LLC | Added | $122.6m1.9m shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $92.1m1.4m shares |
| Walleye Trading LLC | Reduced | $76.2m1.2m shares |
| JANE STREET GROUP, LLC | Added | $74.1m1.2m shares |
| PEAK6 LLC | Added | $70.1m1.1m shares |
| Portman Square Capital LLP | Added | $46.1m720.8k shares |
| Rokos Capital Management LLP | New | $40.3m630.0k shares |
| Saba Capital Management, L.P. | New | $35.2m550.8k shares |
| Twin Tree Management, LP | Reduced | $28.4m443.9k shares |
| MARSHALL WACE, LLP | New | $27.2m424.7k 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 in Q2 2025
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 |
|---|---|---|---|---|---|
| Q3 2023 | 0 | — | 1 | $98.5k | $98.5k |
| Q4 2023 | 0 | — | 1 | $2.8m | — |
| Q1 2024 | 0 | — | 2 | $848.5k | $848.5k |
| Q2 2024 | 0 | — | 3 | $2.2m | $265.4k |
| Q3 2024 | 0 | — | 3 | $6.3m | $5.6m |
| Q4 2024 | 0 | — | 3 | $7.8m | $5.5m |
| Q1 2025 | 0 | — | 1 | $88.4k | $88.4k |
| Q2 2025 | 0 | — | 2 | $657.5k | $657.5k |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2025-06-17 | Zamiska Gene M. SVP & Princ. Acctg Officer | Sold plan | $14.2k245 shares |
| 2025-06-05 | Zamiska Gene M. SVP & Princ. Acctg Officer | Sold plan | $94.9k1.7k shares |
| 2025-05-13 | Tan Irving Chief Executive Officer, director | Sold plan | $548.4k11.4k 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 2025
| Manager | Shares | Change |
|---|---|---|
| VANGUARD GROUP INC 0.04% of their portfolio | 43.0m $2.8bn | Added +100.7k |
| BlackRock, Inc. 0.04% of their portfolio | 35.0m $2.2bn | Added +4.9m |
| FMR LLC 0.12% of their portfolio | 32.3m $2.1bn | Added +4.7m |
| BANK OF AMERICA CORP /DE/ 0.13% of their portfolio | 25.9m $1.7bn | Added +7.6m |
| STATE STREET CORP 0.04% of their portfolio | 15.2m $971.7m | Added +288.3k |
| UBS Group AG 0.15% of their portfolio | 11.4m $731.2m | Reduced -5.7m |
| JPMORGAN CHASE & CO 0.05% of their portfolio | 11.3m $723.6m | Reduced -8.6m |
| FIL Ltd 0.57% of their portfolio | 10.4m $667.1m | Added +2.9m |
| GEODE CAPITAL MANAGEMENT, LLC 0.04% of their portfolio | 9.3m $593.0m | Added +186.0k |
| AMERIPRISE FINANCIAL INC 0.14% of their portfolio | 9.1m $579.7m | Added +1.2m |
| MORGAN STANLEY 0.03% of their portfolio | 7.8m $500.8m | Added +1.3m |
| Slate Path Capital LP 6.66% of their portfolio | 6.0m $386.4m | Reduced -1.6m |
| Holocene Advisors, LP 0.87% of their portfolio | 5.5m $354.2m | Added +431.4k |
| Invesco Ltd. 0.06% of their portfolio | 5.3m $337.1m | Reduced -491.9k |
| DNB Asset Management AS 1.28% of their portfolio | 4.8m $309.8m | Reduced -734.4k |
| ROYAL BANK OF CANADA 0.03% of their portfolio | 4.8m $304.6m | Added +3.2m |
| GOLDMAN SACHS GROUP INC 0.04% of their portfolio | 4.1m $262.5m | Added +2.8m |
| Balyasny Asset Management L.P. 0.58% of their portfolio | 4.0m $255.5m | Added +1.7m |
| Maple Rock Capital Partners Inc. 11.94% of their portfolio | 3.7m $239.0m | Added +545.5k |
| Impactive Capital LP 10.30% of their portfolio | 3.6m $228.5m | Added +2.9m |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.03% of their portfolio | 3.5m $225.9m | Reduced -2.0m |
| CITADEL ADVISORS LLC 0.20% of their portfolio | 3.5m $225.0m | Reduced -381.3k |
| NORGES BANK 0.03% of their portfolio | 3.4m $220.7m | Reduced -1.6m |
| NORTHERN TRUST CORP 0.03% of their portfolio | 3.4m $218.9m | Reduced -28.5k |
| DIMENSIONAL FUND ADVISORS LP 0.05% of their portfolio | 3.4m $217.7m | Added +468.6k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.04% of their portfolio | 3.2m $205.0m | Reduced -129.7k |
| Soroban Capital Partners LP 1.91% of their portfolio | 3.1m $195.9m | Added +2.9m |
| D. E. Shaw & Co., Inc. 0.19% of their portfolio | 2.9m $186.0m | Added +2.9m |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.03% of their portfolio | 2.4m $155.3m | Added +58.8k |
| Elliott Investment Management L.P. 1.18% of their portfolio | 2.2m $144.0m | Unchanged |
| DEUTSCHE BANK AG\ 0.05% of their portfolio | 2.2m $140.7m | Reduced -1.2m |
| Bank of New York Mellon Corp 0.02% of their portfolio | 2.0m $130.4m | Reduced -117.3k |
| Legal & General Group Plc 0.03% of their portfolio | 1.9m $122.3m | Reduced -684.8k |
| AMF Tjanstepension AB 0.79% of their portfolio | 1.9m $119.4m | Reduced -2.3k |
| ALLIANCEBERNSTEIN L.P. 0.04% of their portfolio | 1.7m $111.1m | Reduced -1.2m |
| CITIGROUP INC 0.07% of their portfolio | 1.6m $101.0m | Added +542.9k |
| BNP PARIBAS FINANCIAL MARKETS 0.07% of their portfolio | 1.5m $95.4m | Reduced -193.8k |
| NEUBERGER BERMAN GROUP LLC 0.07% of their portfolio | 1.5m $93.0m | Added +724.9k |
| PARNASSUS INVESTMENTS, LLC 0.21% of their portfolio | 1.4m $92.0m | Reduced -1.1m |
| Pacer Advisors, Inc. 0.22% of their portfolio | 1.4m $88.3m | Added +1.3m |
| LMR Partners LLP 1.37% of their portfolio | 1.4m $88.0m | Added +389.5k |
| LSV ASSET MANAGEMENT 0.21% of their portfolio | 1.4m $87.9m | Added +196.1k |
| Nuveen, LLC 0.02% of their portfolio | 1.4m $87.6m | Added +360.3k |
| AQR CAPITAL MANAGEMENT LLC 0.06% of their portfolio | 1.2m $78.3m | Added +784.6k |
| Amundi 0.03% of their portfolio | 1.2m $79.3m | Reduced -1.3m |
| HSBC HOLDINGS PLC 0.05% of their portfolio | 1.1m $73.6m | Reduced -842.2k |
| Rokos Capital Management LLP 1.17% of their portfolio | 1.1m $69.9m | New |
| Atalan Capital Partners, LP 5.33% of their portfolio | 1.1m $69.4m | Reduced -525.2k |
| PRIMECAP MANAGEMENT CO/CA/ 0.05% of their portfolio | 1.1m $68.6m | Reduced -49.5k |
| WELLS FARGO & COMPANY/MN 0.01% of their portfolio | 1.0m $67.1m | Added +140.0k |
| Swiss National Bank 0.04% of their portfolio | 1.0m $67.0m | Added +71.6k |
| Capitolis Liquid Global Markets LLC 0.47% of their portfolio | 1.0m $64.0m | New |
| BARCLAYS PLC 0.02% of their portfolio | 983.2k $62.9m | Reduced -132.5k |
| FIRST TRUST ADVISORS LP 0.05% of their portfolio | 936.3k $59.9m | Added +722.7k |
| Alyeska Investment Group, L.P. 0.21% of their portfolio | 907.9k $58.1m | Reduced -4.1m |
| WESTFIELD CAPITAL MANAGEMENT CO LP 0.23% of their portfolio | 862.2k $55.2m | Reduced -13.5k |
| Artemis Investment Management LLP 0.70% of their portfolio | 855.9k $54.8m | Added +20.6k |
| Point72 Asset Management, L.P. 0.13% of their portfolio | 836.0k $53.5m | New |
| MANGROVE PARTNERS IM, LLC 5.66% of their portfolio | 824.3k $52.7m | New |
| SG Americas Securities, LLC 0.23% of their portfolio | 804.6k $51.5m | Added +610.5k |
| Sumitomo Mitsui Trust Group, Inc. 0.03% of their portfolio | 800.1k $51.2m | Added +20.5k |
| Allianz Asset Management GmbH 0.07% of their portfolio | 763.6k $48.9m | Reduced -609.4k |
| Castle Hook Partners LP 0.67% of their portfolio | 712.7k $45.6m | New |
| VICTORY CAPITAL MANAGEMENT INC 0.03% of their portfolio | 700.6k $44.8m | Added +574.7k |
| Park West Asset Management LLC 3.42% of their portfolio | 700.0k $44.8m | Reduced -150.0k |
| RHUMBLINE ADVISERS 0.04% of their portfolio | 680.3k $43.5m | Added +5.4k |
| Alta Park Capital, LP 5.24% of their portfolio | 663.7k $42.5m | New |
| Mitsubishi UFJ Asset Management Co., Ltd. 0.03% of their portfolio | 659.5k $42.2m | Added +38.3k |
| HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND 0.08% of their portfolio | 641.7k $41.1m | Added +384.3k |
| GLENVIEW CAPITAL MANAGEMENT, LLC 1.09% of their portfolio | 600.6k $38.4m | Reduced -185.9k |
| PRINCIPAL FINANCIAL GROUP INC 0.02% of their portfolio | 551.4k $35.3m | Added +159.7k |
| California Public Employees Retirement System 0.02% of their portfolio | 546.6k $35.0m | Added +158.8k |
| DEPRINCE RACE & ZOLLO INC 0.72% of their portfolio | 543.2k $34.8m | Reduced -78.4k |
| Schonfeld Strategic Advisors LLC 0.26% of their portfolio | 538.6k $34.5m | Added +499.4k |
| BANK OF MONTREAL /CAN/ 0.02% of their portfolio | 537.0k $34.4m | Reduced -457.3k |
| HIGHLAND PEAK CAPITAL, LLC 13.69% of their portfolio | 523.2k $33.5m | Reduced -187.0k |
| Meridiem Capital Partners LP 2.40% of their portfolio | 519.8k $33.3m | Added +70.8k |
| ARS Investment Partners, LLC 2.36% of their portfolio | 505.3k $32.3m | New |
| Gotham Asset Management, LLC 0.19% of their portfolio | 505.2k $32.3m | Added +138.3k |
| Nearwater Capital Markets, Ltd 0.52% of their portfolio | 504.0k $32.3m | New |
| Bahl & Gaynor LLC 0.16% of their portfolio | 491.1k $31.4m | New |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.03% of their portfolio | 489.2k $31.3m | Reduced -6.5k |
| TWO SIGMA INVESTMENTS, LP 0.06% of their portfolio | 486.5k $31.1m | Reduced -105.4k |
| Ceredex Value Advisors LLC 0.64% of their portfolio | 468.1k $30.0m | New |
| Talos Eurisko Asset Management LP 6.91% of their portfolio | 451.0k $28.9m | New |
| MACKENZIE FINANCIAL CORP 0.04% of their portfolio | 442.4k $28.3m | Reduced -13.3k |
| Russell Investments Group, Ltd. 0.03% of their portfolio | 392.2k $25.1m | Reduced -27.7k |
| LOOMIS SAYLES & CO L P 0.03% of their portfolio | 381.4k $24.4m | Added +13.0k |
| Wolf Hill Capital Management, LP 1.99% of their portfolio | 375.0k $24.0m | New |
| MILLENNIUM MANAGEMENT LLC 0.02% of their portfolio | 374.3k $24.0m | Added +288.8k |
| NOMURA ASSET MANAGEMENT CO LTD 0.06% of their portfolio | 369.8k $23.7m | Added +260.4k |
| Squarepoint Ops LLC 0.05% of their portfolio | 368.3k $23.6m | Reduced -1.3m |
| Robeco Institutional Asset Management B.V. 0.04% of their portfolio | 361.7k $23.1m | Added +235.7k |
| BANK OF NOVA SCOTIA 0.05% of their portfolio | 359.1k $23.0m | Added +349.8k |
| National Pension Service 0.02% of their portfolio | 354.3k $22.7m | Unchanged |
| AXA S.A. 0.06% of their portfolio | 345.4k $22.1m | Added +143.2k |
| 683 Capital Management, LLC 2.20% of their portfolio | 339.0k $21.7m | Reduced -161.0k |
| WORLDQUANT MILLENNIUM ADVISORS LLC 0.11% of their portfolio | 336.6k $21.5m | New |
| KEYSTONE INVESTORS PTE LTD 4.39% of their portfolio | 332.6k $21.3m | New |
| STATE BOARD OF ADMINISTRATION OF FLORIDA RETIREMENT SYSTEM 0.04% of their portfolio | 325.1k $20.8m | Added +4.2k |