Western Digital Corporation
MX ˙ BMV ˙ US9581021055
SecurityMX:WDC / Western Digital Corporation
InstitutionCapital Fund Management S.a.
Latest Disclosed Ownership100,563 shares
Latest Disclosed Value $ 27,201,285
Capital Fund Management S.a. ownership in WDC / Western Digital Corporation

On May 14, 2026 - Capital Fund Management S.a. filed a 13F-HR form disclosing ownership of 100,563 shares of Western Digital Corporation (MX:WDC) valued at $27,201,285 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 227,097 shares of Western Digital Corporation. This represents a change in shares of -55.72% during the quarter.

Capital Fund Management S.a. has a history of taking positions in derivatives of the underlying security (WDC) in the form of stock options. The firm currently holds call options representing 100,600 of underlying shares valued at $27,211,294 USD and put options representing 128,700 of underlying shares valued at $34,812,063 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Institutional Put/Call Ratios
(Premium Subscription Required)

In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

MX:WDC / Western Digital Corporation Historical Put/Call Ratio
Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-14 2026-03-31 13F WESTERN DIGITAL CORP COM WESTERN DIGITAL CORP COM 958102105 100,563 -126,534 -55.72 27,201 -30.47 0.1229
2026-02-17 2025-12-31 13F WESTERN DIGITAL CORP COM WESTERN DIGITAL CORP COM 958102105 227,097 946 0.42 39,122 44.09 0.1087
2025-11-13 2025-09-30 13F WESTERN DIGITAL COM 958102105 226,151 226,151 27,152 0.0711
2025-08-13 2025-06-30 13F WESTERN DIGITAL COM 958102105 0 -70,525 -100.00 0 -100.00
2025-05-14 2025-03-31 13F WESTERN DIGITAL COM 958102105 70,525 70,525 2,851 0.0082
2025-02-13 2024-12-31 13F WESTERN DIGITAL COM 958102105 0 -100,162 -100.00 0 -100.00
2024-11-13 2024-09-30 13F WESTERN DIGITAL COM 958102105 100,162 -310,844 -75.63 6,840 -78.04 0.0187
2024-08-13 2024-06-30 13F WESTERN DIGITAL COM 958102105 411,006 311,092 311.36 31,142 356.75 0.0916
2024-05-15 2024-03-31 13F WESTERN DIGITAL COM 958102105 99,914 -29,254 -22.65 6,818 0.80 0.0197
2024-02-14 2023-12-31 13F WESTERN DIGITAL COM 958102105 129,168 -40,783 -24.00 6,765 -12.77 0.0182
2023-11-14 2023-09-30 13F WESTERN DIGITAL COM 958102105 169,951 -3,640 -2.10 7,755 17.77 0.0268
2023-08-14 2023-06-30 13F WESTERN DIGITAL COM 958102105 173,591 135,804 359.39 6,584 362.68 0.0267
2023-05-15 2023-03-31 13F WESTERN DIGITAL COM 958102105 37,787 -58,624 -60.81 1,423 -53.21 0.0068
2023-02-13 2022-12-31 13F WESTERN DIGITAL COM 958102105 96,411 -55,331 -36.46 3,042 -38.43 0.0204
2022-11-14 2022-09-30 13F WESTERN DIGITAL COM 958102105 151,742 15,971 11.76 4,939 -18.85 0.0388
2022-08-12 2022-06-30 13F WESTERN DIGITAL COM 958102105 135,771 35,424 35.30 6,087 22.16 0.0554
2022-05-12 2022-03-31 13F WESTERN DIGITAL COM 958102105 100,347 -102,917 -50.63 4,982 -62.41 0.0407
2022-02-10 2021-12-31 13F WESTERN DIGITAL COM 958102105 203,264 174,815 614.49 13,255 725.79 0.0954
2021-11-12 2021-09-30 13F WESTERN DIGITAL COM 958102105 28,449 -37,445 -56.83 1,606 -65.77 0.0119
2021-08-12 2021-06-30 13F WESTERN DIGITAL COM 958102105 65,894 -1,201 -1.79 4,690 4.71 0.0371
2021-05-14 2021-03-31 13F WESTERN DIGITAL COM 958102105 67,095 -314,884 -82.43 4,479 -78.83 0.0495
2021-02-12 2020-12-31 13F WESTERN DIGITAL COM 958102105 381,979 277,243 264.71 21,158 452.69 0.1995
2020-11-13 2020-09-30 13F WESTERN DIGITAL COM 958102105 104,736 -264,119 -71.61 3,828 -76.49 0.0473
2020-08-13 2020-06-30 13F WESTERN DIGITAL COM 958102105 368,855 240,269 186.85 16,285 204.26 0.2584
2020-05-13 2020-03-31 13F Western Digital COM 958102105 128,586 -148,804 -53.64 5,352 -69.60 0.0828
2020-02-13 2019-12-31 13F Western Digital COM 958102105 277,390 277,390 17,606 0.1385
2018-11-14 2018-09-30 13F Western Digital COM 958102105 0 -221,688 -100.00 0 -100.00
2018-08-14 2018-06-30 13F Western Digital COM 958102105 221,688 1,100 0.50 17,161 -15.69 0.0895
2018-05-15 2018-03-31 13F Western Digital COM 958102105 220,588 -388,339 -63.77 20,354 -57.97 0.1222
2018-02-09 2017-12-31 13F Western Digital COM 958102105 608,927 591,309 3,356.28 48,428 3,081.87 0.2670
2017-11-13 2017-09-30 13F Western Digital COM 958102105 17,618 15,054 587.13 1,522 570.48 0.0109
2017-08-10 2017-06-30 13F Western Digital COM 958102105 2,564 2,564 227 0.0018
2016-10-31 2016-09-30 13F Western Digital COM 958102105 0 -67,425 -100.00 0 -100.00
2016-07-27 2016-06-30 13F Western Digital COM 958102105 67,425 -813,016 -92.34 3,187 -92.34 0.0299
2016-05-02 2016-03-31 13F Western Digital COM 958102105 880,441 880,441 0.00 41,592 0.4040
2016-01-28 2015-12-31 13F Western Digital COM 958102105 0 0 0 0.0000
2015-10-27 2015-09-30 13F Western Digital COM 958102105 0 -116,692 -100.00 0 -100.00
2015-07-28 2015-06-30 13F Western Digital COM 958102105 116,692 -26,774 -18.66 9,151 -29.91 0.1161
2015-04-28 2015-03-31 13F Western Digital COM 958102105 143,466 143,466 0.00 13,057 0.1781
2015-01-28 2014-12-31 13F Western Digital COM 958102105 0 -570,053 -100.00 0 -100.00
2014-10-31 2014-09-30 13F Western Digital COM 958102105 570,053 222,600 64.07 55,478 72.99 0.6211
2014-08-01 2014-06-30 13F Western Digital COM 958102105 347,453 3,616 1.05 32,070 1.58 0.3386
2014-05-14 2014-03-31 13F Western Digital COM 958102105 343,837 -190,069 -35.60 31,571 -29.52 0.3862
2014-01-31 2013-12-31 13F Western Digital COM 958102105 533,906 501,027 1,523.85 44,795 2,048.44 0.5541
2013-10-31 2013-09-30 13F Western Digital COM 958102105 32,879 -118,583 -78.29 2,085 -77.83 0.0288
2013-07-31 2013-06-30 13F Western Digital COM 958102105 151,462 151,462 9,404 0.1436
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-14 2026-03-31 13F WESTERN DIGITAL CORP COM WESTERN DIGITAL CORP COM Call 100,600 -61.87 27,211 -40.12 n/a n/a n/a
2026-02-17 2025-12-31 13F WESTERN DIGITAL CORP COM WESTERN DIGITAL CORP COM Call 263,800 26.77 45,445 81.89 n/a n/a n/a
2025-11-13 2025-09-30 13F WESTERN DIGITAL COM Call 208,100 55.41 24,984 191.60 n/a n/a n/a
2025-08-13 2025-06-30 13F WESTERN DIGITAL COM Call 133,900 -3.39 8,568 52.92 n/a n/a n/a
2025-05-14 2025-03-31 13F WESTERN DIGITAL COM Call 138,600 51.81 5,604 2.92 n/a n/a n/a
2025-02-13 2024-12-31 13F WESTERN DIGITAL COM Call 91,300 -71.95 5,444 -75.51 n/a n/a n/a
2024-11-13 2024-09-30 13F WESTERN DIGITAL COM Call 325,500 -13.18 22,228 -21.75 n/a n/a n/a
2024-08-13 2024-06-30 13F WESTERN DIGITAL COM Call 374,900 1,982.78 28,406 2,213.19 n/a n/a n/a
2024-05-15 2024-03-31 13F WESTERN DIGITAL COM Call 18,000 -10.00 1,228 17.29 n/a n/a n/a
2024-02-14 2023-12-31 13F WESTERN DIGITAL COM Call 20,000 1,047 n/a n/a n/a
2023-11-14 2023-09-30 13F WESTERN DIGITAL COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2023-08-14 2023-06-30 13F WESTERN DIGITAL COM Call 22,200 -84.55 842 -84.44 n/a n/a n/a
2023-05-15 2023-03-31 13F WESTERN DIGITAL COM Call 143,700 -75.88 5,413 -71.20 n/a n/a n/a
2023-02-13 2022-12-31 13F WESTERN DIGITAL COM Call 595,700 270.00 18,794 258.66 n/a n/a n/a
2022-11-14 2022-09-30 13F WESTERN DIGITAL COM Call 161,000 5,241 n/a n/a n/a
2022-08-12 2022-06-30 13F WESTERN DIGITAL COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2022-05-12 2022-03-31 13F WESTERN DIGITAL COM Call 61,200 201.48 3,039 129.63 n/a n/a n/a
2022-02-10 2021-12-31 13F WESTERN DIGITAL COM Call 20,300 -12.50 1,324 1.07 n/a n/a n/a
2021-11-12 2021-09-30 13F WESTERN DIGITAL COM Call 23,200 -39.58 1,309 -52.09 n/a n/a n/a
2021-08-12 2021-06-30 13F WESTERN DIGITAL COM Call 38,400 -72.92 2,733 -71.14 n/a n/a n/a
2021-05-14 2021-03-31 13F WESTERN DIGITAL COM Call 141,800 -3.73 9,465 16.02 n/a n/a n/a
2021-02-12 2020-12-31 13F WESTERN DIGITAL COM Call 147,300 6.20 8,159 60.94 n/a n/a n/a
2020-11-13 2020-09-30 13F WESTERN DIGITAL COM Call 138,700 -55.76 5,069 -63.38 n/a n/a n/a
2020-08-13 2020-06-30 13F WESTERN DIGITAL COM Call 313,500 -9.42 13,841 -3.92 n/a n/a n/a
2020-05-13 2020-03-31 13F Western Digital COM Call 346,100 -36.47 14,405 -58.34 n/a n/a n/a
2020-02-13 2019-12-31 13F Western Digital COM Call 544,800 -27.77 34,578 -23.14 n/a n/a n/a
2019-11-13 2019-09-30 13F Western Digital COM Call 754,300 -7.70 44,986 15.77 n/a n/a n/a
2019-08-12 2019-06-30 13F Western Digital COM Call 817,200 -36.31 38,858 -36.99 n/a n/a n/a
2019-05-13 2019-03-31 13F/A Western Digital COM Call 1,283,100 12.31 61,666 46.00 n/a n/a n/a
2019-05-13 2019-03-31 13F Western Digital COM Call 1,142,500 42,238 n/a n/a n/a
2019-02-13 2018-12-31 13F Western Digital COM Call 1,142,500 164.71 42,238 67.17 n/a n/a n/a
2018-11-14 2018-09-30 13F Western Digital COM Call 431,600 12,978.79 25,266 9,808.24 n/a n/a n/a
2018-08-14 2018-06-30 13F Western Digital COM Call 3,300 255 n/a n/a n/a
2018-05-15 2018-03-31 13F Western Digital COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2018-02-09 2017-12-31 13F Western Digital COM Call 15,700 -89.23 1,249 -90.08 n/a n/a n/a
2017-11-13 2017-09-30 13F Western Digital COM Call 145,800 -47.84 12,597 -49.13 n/a n/a n/a
2017-08-10 2017-06-30 13F Western Digital COM Call 279,500 78.25 24,764 91.36 n/a n/a n/a
2017-05-03 2017-03-31 13F Western Digital COM Call 156,800 -54.22 12,941 -44.39 n/a n/a n/a
2017-02-08 2016-12-31 13F Western Digital COM Call 342,500 17.29 23,273 36.31 n/a n/a n/a
2016-10-31 2016-09-30 13F Western Digital COM Call 292,000 -47.90 17,073 -35.55 n/a n/a n/a
2016-07-27 2016-06-30 13F Western Digital COM Call 560,500 40.48 26,489 40.53 n/a n/a n/a
2016-05-02 2016-03-31 13F Western Digital COM Call 399,000 276.42 18,849 196.14 n/a n/a n/a
2016-01-28 2015-12-31 13F Western Digital COM Call 106,000 281.29 6,365 188.27 n/a n/a n/a
2015-10-27 2015-09-30 13F Western Digital COM Call 27,800 2,208 n/a n/a n/a
2015-01-28 2014-12-31 13F Western Digital COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2014-10-31 2014-09-30 13F Western Digital COM Call 2,300 -41.03 224 -37.78 n/a n/a n/a
2014-08-01 2014-06-30 13F Western Digital COM Call 3,900 -64.86 360 -64.67 n/a n/a n/a
2014-05-14 2014-03-31 13F Western Digital COM Call 11,100 -73.32 1,019 -70.80 n/a n/a n/a
2014-01-31 2013-12-31 13F Western Digital COM Call 41,600 67.07 3,490 121.03 n/a n/a n/a
2013-10-31 2013-09-30 13F Western Digital COM Call 24,900 -46.45 1,579 -45.31 n/a n/a n/a
2013-07-31 2013-06-30 13F Western Digital COM Call 46,500 2,887 n/a n/a n/a
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-14 2026-03-31 13F WESTERN DIGITAL CORP COM WESTERN DIGITAL CORP COM Put 128,700 -60.12 34,812 -37.38 n/a n/a n/a
2026-02-17 2025-12-31 13F WESTERN DIGITAL CORP COM WESTERN DIGITAL CORP COM Put 322,700 -21.77 55,592 12.25 n/a n/a n/a
2025-11-13 2025-09-30 13F WESTERN DIGITAL COM Put 412,500 37.41 49,525 157.82 n/a n/a n/a
2025-08-13 2025-06-30 13F WESTERN DIGITAL COM Put 300,200 10.25 19,210 74.48 n/a n/a n/a
2025-05-14 2025-03-31 13F WESTERN DIGITAL COM Put 272,300 43.01 11,009 -3.03 n/a n/a n/a
2025-02-13 2024-12-31 13F WESTERN DIGITAL COM Put 190,400 -51.03 11,354 -57.24 n/a n/a n/a
2024-11-13 2024-09-30 13F WESTERN DIGITAL COM Put 388,800 -23.09 26,551 -30.68 n/a n/a n/a
2024-08-13 2024-06-30 13F WESTERN DIGITAL COM Put 505,500 672.94 38,302 758.38 n/a n/a n/a
2024-05-15 2024-03-31 13F WESTERN DIGITAL COM Put 65,400 31.33 4,463 71.09 n/a n/a n/a
2024-02-14 2023-12-31 13F WESTERN DIGITAL COM Put 49,800 2,608 n/a n/a n/a
2023-11-14 2023-09-30 13F WESTERN DIGITAL COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2023-08-14 2023-06-30 13F WESTERN DIGITAL COM Put 11,800 -93.26 448 -93.22 n/a n/a n/a
2023-05-15 2023-03-31 13F WESTERN DIGITAL COM Put 175,100 -62.34 6,596 -55.03 n/a n/a n/a
2023-02-13 2022-12-31 13F WESTERN DIGITAL COM Put 464,900 496.03 14,668 477.90 n/a n/a n/a
2022-11-14 2022-09-30 13F WESTERN DIGITAL COM Put 78,000 449.30 2,539 299.06 n/a n/a n/a
2022-08-12 2022-06-30 13F WESTERN DIGITAL COM Put 14,200 -86.69 637 -87.99 n/a n/a n/a
2022-05-12 2022-03-31 13F WESTERN DIGITAL COM Put 106,700 575.32 5,298 414.27 n/a n/a n/a
2022-02-10 2021-12-31 13F WESTERN DIGITAL COM Put 15,800 -43.37 1,030 -34.56 n/a n/a n/a
2021-11-12 2021-09-30 13F WESTERN DIGITAL COM Put 27,900 -45.29 1,575 -56.63 n/a n/a n/a
2021-08-12 2021-06-30 13F WESTERN DIGITAL COM Put 51,000 -58.02 3,630 -55.25 n/a n/a n/a
2021-05-14 2021-03-31 13F WESTERN DIGITAL COM Put 121,500 -48.25 8,110 -37.64 n/a n/a n/a
2021-02-12 2020-12-31 13F WESTERN DIGITAL COM Put 234,800 22.23 13,006 85.23 n/a n/a n/a
2020-11-13 2020-09-30 13F WESTERN DIGITAL COM Put 192,100 -35.01 7,021 -46.20 n/a n/a n/a
2020-08-13 2020-06-30 13F WESTERN DIGITAL COM Put 295,600 -16.31 13,051 -11.22 n/a n/a n/a
2020-05-13 2020-03-31 13F Western Digital COM Put 353,200 -50.55 14,700 -67.57 n/a n/a n/a
2020-02-13 2019-12-31 13F Western Digital COM Put 714,200 37.24 45,330 46.05 n/a n/a n/a
2019-11-13 2019-09-30 13F Western Digital COM Put 520,400 -34.62 31,037 -18.00 n/a n/a n/a
2019-08-12 2019-06-30 13F Western Digital COM Put 796,000 -39.00 37,850 -39.65 n/a n/a n/a
2019-05-13 2019-03-31 13F/A Western Digital COM Put 1,304,900 30.02 62,713 69.02 n/a n/a n/a
2019-05-13 2019-03-31 13F Western Digital COM Put 1,003,600 37,103 n/a n/a n/a
2019-02-13 2018-12-31 13F Western Digital COM Put 1,003,600 71.41 37,103 8.25 n/a n/a n/a
2018-11-14 2018-09-30 13F Western Digital COM Put 585,500 16,163.89 34,275 12,184.95 n/a n/a n/a
2018-08-14 2018-06-30 13F Western Digital COM Put 3,600 28.57 279 8.14 n/a n/a n/a
2018-05-15 2018-03-31 13F Western Digital COM Put 2,800 -93.24 258 -92.17 n/a n/a n/a
2018-02-09 2017-12-31 13F Western Digital COM Put 41,400 -8.20 3,293 -15.50 n/a n/a n/a
2017-11-13 2017-09-30 13F Western Digital COM Put 45,100 -86.51 3,897 -86.85 n/a n/a n/a
2017-08-10 2017-06-30 13F Western Digital COM Put 334,400 73.08 29,628 85.81 n/a n/a n/a
2017-05-03 2017-03-31 13F Western Digital COM Put 193,200 -75.13 15,945 -69.80 n/a n/a n/a
2017-02-08 2016-12-31 13F Western Digital COM Put 776,900 16.83 52,790 35.77 n/a n/a n/a
2016-10-31 2016-09-30 13F Western Digital COM Put 665,000 21.64 38,883 50.49 n/a n/a n/a
2016-07-27 2016-06-30 13F Western Digital COM Put 546,700 60.37 25,837 60.44 n/a n/a n/a
2016-05-02 2016-03-31 13F Western Digital COM Put 340,900 183.14 16,104 122.74 n/a n/a n/a
2016-01-28 2015-12-31 13F Western Digital COM Put 120,400 357.79 7,230 246.10 n/a n/a n/a
2015-10-27 2015-09-30 13F Western Digital COM Put 26,300 651.43 2,089 662.41 n/a n/a n/a
2015-07-28 2015-06-30 13F Western Digital COM Put 3,500 52.17 274 31.10 n/a n/a n/a
2015-04-28 2015-03-31 13F Western Digital COM Put 2,300 209 n/a n/a n/a
2015-01-28 2014-12-31 13F Western Digital COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2014-10-31 2014-09-30 13F Western Digital COM Put 8,100 -50.00 788 -47.29 n/a n/a n/a
2014-08-01 2014-06-30 13F Western Digital COM Put 16,200 -65.89 1,495 -65.72 n/a n/a n/a
2014-05-14 2014-03-31 13F Western Digital COM Put 47,500 -21.49 4,361 -14.09 n/a n/a n/a
2014-01-31 2013-12-31 13F Western Digital COM Put 60,500 124.91 5,076 197.71 n/a n/a n/a
2013-10-31 2013-09-30 13F Western Digital COM Put 26,900 -57.50 1,705 -56.62 n/a n/a n/a
2013-07-31 2013-06-30 13F Western Digital COM Put 63,300 3,930 n/a n/a n/a
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.