Western Digital Corporation
MX ˙ BMV ˙ US9581021055
SecurityMX:WDC / Western Digital Corporation
InstitutionMillennium Management Llc
ManagerIsrael Englander
Latest Disclosed Ownership277,653 shares
Latest Disclosed Value $ 75,102,360
Millennium Management Llc ownership in WDC / Western Digital Corporation

On May 15, 2026 - Millennium Management Llc filed a 13F-HR form disclosing ownership of 277,653 shares of Western Digital Corporation (MX:WDC) valued at $75,102,360 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 317,205 shares of Western Digital Corporation. This represents a change in shares of -12.47% during the quarter.

Millennium Management Llc 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 159,400 of underlying shares valued at $43,116,106 USD and put options representing 297,000 of underlying shares valued at $80,335,530 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
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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)
2026-05-15 2026-03-31 13F WESTERN DIGITAL COM 958102105 277,653 -39,552 -12.47 75,102 37.44 0.0313
2026-02-17 2025-12-31 13F WESTERN DIGITAL COM 958102105 317,205 -914,620 -74.25 54,645 -63.05 0.0230
2025-11-14 2025-09-30 13F WESTERN DIGITAL COM 958102105 1,231,825 857,489 229.07 147,893 517.43 0.0631
2025-08-14 2025-06-30 13F WESTERN DIGITAL COM 958102105 374,336 288,786 337.56 23,954 592.68 0.0116
2025-05-15 2025-03-31 13F WESTERN DIGITAL COM 958102105 85,550 -1,046,512 -92.44 3,459 -94.88 0.0018
2025-02-14 2024-12-31 13F WESTERN DIGITAL COM 958102105 1,132,062 -1,489,414 -56.82 67,505 -62.29 0.0330
2024-11-14 2024-09-30 13F WESTERN DIGITAL COM 958102105 2,621,476 -2,389,837 -47.69 179,021 -52.85 0.0849
2024-08-14 2024-06-30 13F WESTERN DIGITAL COM 958102105 5,011,313 239,108 5.01 379,707 16.60 0.1758
2024-05-15 2024-03-31 13F WESTERN DIGITAL COM 958102105 4,772,205 -5,711,316 -54.48 325,655 -40.68 0.1391
2024-02-14 2023-12-31 13F WESTERN DIGITAL COM 958102105 10,483,521 3,917,122 59.65 549,022 83.24 0.2375
2023-11-14 2023-09-30 13F WESTERN DIGITAL COM 958102105 6,566,399 -42,544 -0.64 299,625 19.53 0.1512
2023-08-14 2023-06-30 13F WESTERN DIGITAL COM 958102105 6,608,943 -1,491,497 -18.41 250,677 -17.85 0.1236
2023-05-15 2023-03-31 13F WESTERN DIGITAL COM 958102105 8,100,440 4,992,612 160.65 305,144 211.21 0.1750
2023-02-14 2022-12-31 13F WESTERN DIGITAL COM 958102105 3,107,828 1,367,858 78.61 98,052 73.13 0.0542
2022-11-14 2022-09-30 13F WESTERN DIGITAL COM 958102105 1,739,970 -740,637 -29.86 56,636 -49.07 0.0335
2022-08-15 2022-06-30 13F WESTERN DIGITAL COM 958102105 2,480,607 961,290 63.27 111,206 47.42 0.0690
2022-05-16 2022-03-31 13F WESTERN DIGITAL COM 958102105 1,519,317 423,399 38.63 75,434 5.55 0.0400
2022-02-14 2021-12-31 13F WESTERN DIGITAL COM 958102105 1,095,918 238,695 27.85 71,465 47.71 0.0363
2021-11-15 2021-09-30 13F WESTERN DIGITAL COM 958102105 857,223 -2,347,983 -73.26 48,382 -78.79 0.0290
2021-08-16 2021-06-30 13F WESTERN DIGITAL COM 958102105 3,205,206 808,139 33.71 228,115 42.57 0.1399
2021-05-17 2021-03-31 13F WESTERN DIGITAL COM 958102105 2,397,067 2,084,322 666.46 160,004 823.65 0.1145
2021-02-16 2020-12-31 13F WESTERN DIGITAL COM 958102105 312,745 -566,691 -64.44 17,323 -46.11 0.0125
2020-11-16 2020-09-30 13F WESTERN DIGITAL COM 958102105 879,436 574,364 188.27 32,143 138.64 0.0396
2020-08-14 2020-06-30 13F WESTERN DIGITAL COM 958102105 305,072 -213,683 -41.19 13,469 -37.62 0.0185
2020-05-14 2020-03-31 13F WESTERN DIGITAL COM 958102105 518,755 488,808 1,632.24 21,591 1,035.77 0.0485
2020-02-14 2019-12-31 13F WESTERN DIGITAL COM 958102105 29,947 -276,513 -90.23 1,901 -89.60 0.0024
2019-11-14 2019-09-30 13F WESTERN DIGITAL COM 958102105 306,460 306,460 923.34 18,277 861.44 0.0289
2019-08-15 2019-06-30 13F/A-1 WESTERN DIGITAL COM 958102105 0 -33,293 -100.00 0 -100.00
2019-05-14 2019-03-31 13F WESTERN DIGITAL COM 958102105 33,293 33,293 1,600 0.0024
2019-02-15 2018-12-31 13F/A-1 WESTERN DIGITAL COM 958102105 0 -27,600 -100.00 0 -100.00
2018-11-14 2018-09-30 13F WESTERN DIGITAL COM 958102105 27,600 -242,701 -89.79 1,616 -92.28 0.0020
2018-08-14 2018-06-30 13F WESTERN DIGITAL COM 958102105 270,301 -1,130,428 -80.70 20,924 -83.81 0.0273
2018-05-15 2018-03-31 13F WESTERN DIGITAL COM 958102105 1,400,729 -360,714 -20.48 129,245 -7.74 0.1725
2018-02-14 2017-12-31 13F WESTERN DIGITAL COM 958102105 1,761,443 854,852 94.29 140,088 78.85 0.1934
2017-11-14 2017-09-30 13F WESTERN DIGITAL COM 958102105 906,591 903,385 28,177.95 78,329 27,480.63 0.1193
2017-08-14 2017-06-30 13F WESTERN DIGITAL COM 958102105 3,206 -458,261 -99.31 284 -99.25 0.0005
2017-05-15 2017-03-31 13F WESTERN DIGITAL COM 958102105 461,467 -24,060 -4.96 38,085 15.44 0.0698
2017-02-14 2016-12-31 13F WESTERN DIGITAL COM 958102105 485,527 59,045 13.84 32,992 32.31 0.0691
2016-11-14 2016-09-30 13F WESTERN DIGITAL COM 958102105 426,482 -781,546 -64.70 24,936 -56.32 0.0418
2016-08-15 2016-06-30 13F WESTERN DIGITAL COM 958102105 1,208,028 871,854 259.35 57,091 259.49 0.1307
2016-05-16 2016-03-31 13F WESTERN DIGITAL COM 958102105 336,174 97,436 40.81 15,881 10.78 0.0397
2016-02-16 2015-12-31 13F WESTERN DIGITAL COM 958102105 238,738 -700,910 -74.59 14,336 -80.79 0.0301
2015-11-16 2015-09-30 13F WESTERN DIGITAL COM 958102105 939,648 338,943 56.42 74,646 58.46 0.1445
2015-08-14 2015-06-30 13F WESTERN DIGITAL COM 958102105 600,705 36,197 6.41 47,107 -8.31 0.0891
2015-05-15 2015-03-31 13F WESTERN DIGITAL COM 958102105 564,508 218,896 63.34 51,376 34.28 0.0956
2015-02-17 2014-12-31 13F WESTERN DIGITAL COM 958102105 345,612 -597,263 -63.34 38,259 -58.31 0.0811
2014-11-14 2014-09-30 13F WESTERN DIGITAL COM 958102105 942,875 189,202 25.10 91,761 31.91 0.2322
2014-08-14 2014-06-30 13F WESTERN DIGITAL COM 958102105 753,673 460,540 157.11 69,564 158.46 0.1927
2014-05-15 2014-03-31 13F WESTERN DIGITAL COM 958102105 293,133 -97,022 -24.87 26,915 -17.78 0.0780
2014-02-14 2013-12-31 13F WESTERN DIGITAL COM 958102105 390,155 -21,679 -5.26 32,734 25.37 0.1033
2013-11-14 2013-09-30 13F WESTERN DIGITAL COM 958102105 411,834 -213,678 -34.16 26,110 -32.77 0.0841
2013-08-14 2013-06-30 13F WESTERN DIGITAL COM 958102105 625,512 625,512 38,838 0.1191
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
(%)
2026-05-15 2026-03-31 13F WESTERN DIGITAL COM Call 159,400 -46.37 43,116 -15.79 n/a n/a n/a
2026-02-17 2025-12-31 13F WESTERN DIGITAL COM Call 297,200 259.37 51,199 415.69 n/a n/a n/a
2025-11-14 2025-09-30 13F WESTERN DIGITAL COM Call 82,700 -27.46 9,929 36.11 n/a n/a n/a
2025-08-14 2025-06-30 13F WESTERN DIGITAL COM Call 114,000 -69.62 7,295 -51.92 n/a n/a n/a
2025-05-15 2025-03-31 13F WESTERN DIGITAL COM Call 375,200 -38.78 15,169 -58.49 n/a n/a n/a
2025-02-14 2024-12-31 13F WESTERN DIGITAL COM Call 612,900 281.16 36,547 232.82 n/a n/a n/a
2024-11-14 2024-09-30 13F WESTERN DIGITAL COM Call 160,800 48.34 10,981 33.70 n/a n/a n/a
2024-08-14 2024-06-30 13F WESTERN DIGITAL COM Call 108,400 -39.48 8,213 -32.80 n/a n/a n/a
2024-05-15 2024-03-31 13F WESTERN DIGITAL COM Call 179,100 -64.67 12,222 -53.97 n/a n/a n/a
2024-02-14 2023-12-31 13F WESTERN DIGITAL COM Call 507,000 -14.62 26,552 -2.01 n/a n/a n/a
2023-11-14 2023-09-30 13F WESTERN DIGITAL COM Call 593,800 -42.38 27,095 -30.68 n/a n/a n/a
2023-08-14 2023-06-30 13F WESTERN DIGITAL COM Call 1,030,500 -54.14 39,087 -53.82 n/a n/a n/a
2023-05-15 2023-03-31 13F WESTERN DIGITAL COM Call 2,246,900 -3.65 84,641 15.04 n/a n/a n/a
2023-02-14 2022-12-31 13F WESTERN DIGITAL COM Call 2,332,100 170.80 73,578 162.48 n/a n/a n/a
2022-11-14 2022-09-30 13F WESTERN DIGITAL COM Call 861,200 433.91 28,032 287.66 n/a n/a n/a
2022-08-15 2022-06-30 13F WESTERN DIGITAL COM Call 161,300 7,231 n/a n/a n/a
2022-02-14 2021-12-31 13F WESTERN DIGITAL COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2021-11-15 2021-09-30 13F WESTERN DIGITAL COM Call 185,300 131.62 10,458 83.67 n/a n/a n/a
2021-08-16 2021-06-30 13F WESTERN DIGITAL COM Call 80,000 5,694 n/a n/a n/a
2021-05-17 2021-03-31 13F WESTERN DIGITAL COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2021-02-16 2020-12-31 13F WESTERN DIGITAL COM Call 150,000 8,309 n/a n/a n/a
2020-08-14 2020-06-30 13F WESTERN DIGITAL COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2020-05-14 2020-03-31 13F WESTERN DIGITAL COM Call 12,700 529 n/a n/a n/a
2019-11-14 2019-09-30 13F WESTERN DIGITAL COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2019-08-15 2019-06-30 13F/A WESTERN DIGITAL COM Call 45,000 2,140 n/a n/a n/a
2019-08-14 2019-06-30 13F WESTERN DIGITAL COM Call 45,000 2,140 n/a n/a n/a
2015-02-17 2014-12-31 13F WESTERN DIGITAL COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2014-11-14 2014-09-30 13F WESTERN DIGITAL COM Call 2,200 214 n/a n/a n/a
2014-08-14 2014-06-30 13F WESTERN DIGITAL COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2014-05-15 2014-03-31 13F WESTERN DIGITAL COM Call 100 -97.30 9 -96.17 n/a n/a n/a
2014-02-14 2013-12-31 13F WESTERN DIGITAL COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2013-11-14 2013-09-30 13F WESTERN DIGITAL COM Call 3,700 235 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
(%)
2026-05-15 2026-03-31 13F WESTERN DIGITAL COM Put 297,000 85.28 80,336 190.92 n/a n/a n/a
2026-02-17 2025-12-31 13F WESTERN DIGITAL COM Put 160,300 -45.61 27,615 -21.95 n/a n/a n/a
2025-11-14 2025-09-30 13F WESTERN DIGITAL COM Put 294,700 -15.00 35,382 59.48 n/a n/a n/a
2025-08-14 2025-06-30 13F WESTERN DIGITAL COM Put 346,700 3.52 22,185 63.85 n/a n/a n/a
2025-05-15 2025-03-31 13F WESTERN DIGITAL COM Put 334,900 74.70 13,540 18.45 n/a n/a n/a
2025-02-14 2024-12-31 13F WESTERN DIGITAL COM Put 191,700 -32.17 11,431 -40.77 n/a n/a n/a
2024-11-14 2024-09-30 13F WESTERN DIGITAL COM Put 282,600 -28.31 19,299 -35.39 n/a n/a n/a
2024-08-14 2024-06-30 13F WESTERN DIGITAL COM Put 394,200 -34.92 29,869 -27.74 n/a n/a n/a
2024-05-15 2024-03-31 13F WESTERN DIGITAL COM Put 605,700 -47.40 41,333 -31.47 n/a n/a n/a
2024-02-14 2023-12-31 13F WESTERN DIGITAL COM Put 1,151,600 -0.08 60,309 14.68 n/a n/a n/a
2023-11-14 2023-09-30 13F WESTERN DIGITAL COM Put 1,152,500 26.59 52,589 52.29 n/a n/a n/a
2023-08-14 2023-06-30 13F WESTERN DIGITAL COM Put 910,400 4.26 34,531 4.98 n/a n/a n/a
2023-05-15 2023-03-31 13F WESTERN DIGITAL COM Put 873,200 -40.59 32,893 -29.07 n/a n/a n/a
2023-02-14 2022-12-31 13F WESTERN DIGITAL COM Put 1,469,800 -44.16 46,372 -45.87 n/a n/a n/a
2022-11-14 2022-09-30 13F WESTERN DIGITAL COM Put 2,632,100 -3.36 85,675 -29.83 n/a n/a n/a
2022-08-15 2022-06-30 13F WESTERN DIGITAL COM Put 2,723,500 7.39 122,095 -3.03 n/a n/a n/a
2022-05-16 2022-03-31 13F WESTERN DIGITAL COM Put 2,536,000 -32.79 125,912 -48.83 n/a n/a n/a
2022-02-14 2021-12-31 13F WESTERN DIGITAL COM Put 3,773,200 23.55 246,050 42.74 n/a n/a n/a
2021-11-15 2021-09-30 13F WESTERN DIGITAL COM Put 3,054,100 -0.25 172,373 -20.90 n/a n/a n/a
2021-08-16 2021-06-30 13F WESTERN DIGITAL COM Put 3,061,900 57.25 217,915 67.66 n/a n/a n/a
2021-05-17 2021-03-31 13F WESTERN DIGITAL COM Put 1,947,200 30.05 129,976 56.72 n/a n/a n/a
2021-02-16 2020-12-31 13F WESTERN DIGITAL COM Put 1,497,300 126.69 82,935 243.54 n/a n/a n/a
2020-11-16 2020-09-30 13F WESTERN DIGITAL COM Put 660,500 2,796.93 24,141 2,297.32 n/a n/a n/a
2020-08-14 2020-06-30 13F WESTERN DIGITAL COM Put 22,800 -16.18 1,007 -11.04 n/a n/a n/a
2020-05-14 2020-03-31 13F WESTERN DIGITAL COM Put 27,200 29.52 1,132 -15.08 n/a n/a n/a
2020-02-14 2019-12-31 13F WESTERN DIGITAL COM Put 21,000 121.05 1,333 135.51 n/a n/a n/a
2019-11-14 2019-09-30 13F WESTERN DIGITAL COM Put 9,500 -54.76 566 -57.54 n/a n/a n/a
2016-08-15 2016-06-30 13F WESTERN DIGITAL COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2016-05-16 2016-03-31 13F WESTERN DIGITAL COM Put 50,000 2,362 n/a n/a n/a
2015-02-17 2014-12-31 13F WESTERN DIGITAL COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2014-11-14 2014-09-30 13F WESTERN DIGITAL COM Put 3,700 15.62 360 34.33 n/a n/a n/a
2014-02-14 2013-12-31 13F WESTERN DIGITAL COM Put 3,200 268 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.