Western Digital Corporation
MX ˙ BMV ˙ US9581021055
SecurityMX:WDC / Western Digital Corporation
InstitutionMoors & Cabot, Inc.
Latest Disclosed Ownership2,145 shares
Latest Disclosed Value $ 580,161
Moors & Cabot, Inc. ownership in WDC / Western Digital Corporation

On May 8, 2026 - Moors & Cabot, Inc. filed a 13F-HR form disclosing ownership of 2,145 shares of Western Digital Corporation (MX:WDC) valued at $580,161 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 10, 2026 disclosing 2,113 shares of Western Digital Corporation. This represents a change in shares of 1.51% during the quarter.

Moors & Cabot, Inc. 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 0 of underlying shares valued at $0 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)
2026-05-08 2026-03-31 13F WESTERN DIGITAL COM 958102105 2,145 32 1.51 580 59.78 0.0248
2026-02-10 2025-12-31 13F WESTERN DIGITAL COM 958102105 2,113 73 3.58 364 48.77 0.0156
2025-11-14 2025-09-30 13F WESTERN DIGITAL COM 958102105 2,040 -1,563 -43.38 245 6.09 0.0107
2025-08-06 2025-06-30 13F WESTERN DIGITAL COM 958102105 3,603 3,603 231 0.0107
2025-05-08 2025-03-31 13F WESTERN DIGITAL COM 958102105 0 -3,809 -100.00 0 -100.00
2025-02-07 2024-12-31 13F WESTERN DIGITAL COM 958102105 3,809 -148 -3.74 227 -15.93 0.0108
2024-11-08 2024-09-30 13F WESTERN DIGITAL COM 958102105 3,957 0 0.00 270 -9.70 0.0134
2024-08-09 2024-06-30 13F WESTERN DIGITAL COM 958102105 3,957 -1,665 -29.62 300 -21.93 0.0160
2024-05-08 2024-03-31 13F WESTERN DIGITAL COM 958102105 5,622 0 0.00 384 30.27 0.0208
2024-02-14 2023-12-31 13F WESTERN DIGITAL COM 958102105 5,622 -810 -12.59 294 0.34 0.0183
2023-11-08 2023-09-30 13F WESTERN DIGITAL COM 958102105 6,432 0 0.00 293 20.58 0.0199
2023-08-10 2023-06-30 13F WESTERN DIGITAL COM 958102105 6,432 -100 -1.53 244 -1.22 0.0162
2023-05-05 2023-03-31 13F WESTERN DIGITAL COM 958102105 6,532 -185 -2.75 246 16.59 0.0169
2023-02-10 2022-12-31 13F/A-1 WESTERN DIGITAL COM 958102105 6,717 -2,154 -24.28 212 -26.99 0.0148
2023-02-07 2022-12-31 13F WESTERN DIGITAL COM 958102105 12,524 3,653 817 0.0544
2022-11-08 2022-09-30 13F WESTERN DIGITAL COM 958102105 8,871 -1,417 -13.77 289 -37.31 0.0220
2022-08-08 2022-06-30 13F WESTERN DIGITAL COM 958102105 10,288 -2,896 -21.97 461 -29.62 0.0332
2022-05-13 2022-03-31 13F WESTERN DIGITAL COM 958102105 13,184 460 3.62 655 -21.08 0.0403
2022-02-14 2021-12-31 13F WESTERN DIGITAL COM 958102105 12,724 1,544 13.81 830 31.54 0.0511
2021-12-08 2021-09-30 13F/A-1 WESTERN DIGITAL COM 958102105 11,180 3,751 50.49 631 19.28 0.0396
2021-11-05 2021-09-30 13F WESTERN DIGITAL COM 958102105 25,000 17,571 7 0.0005
2021-08-10 2021-06-30 13F WESTERN DIGITAL COM 958102105 7,429 519 7.51 529 14.75 0.0371
2021-05-12 2021-03-31 13F WESTERN DIGITAL COM 958102105 6,910 -3,875 -35.93 461 -23.17 0.0353
2021-02-11 2020-12-31 13F WESTERN DIGITAL COM 958102105 10,785 903 9.14 600 66.20 0.0504
2020-11-09 2020-09-30 13F WESTERN DIGITAL COM 958102105 9,882 4,400 80.26 361 50.42 0.0340
2020-08-13 2020-06-30 13F WESTERN DIGITAL COM 958102105 5,482 5,482 240 0.0256
2020-05-12 2020-03-31 13F WESTERN DIGITAL COM 958102105 0 -6,587 -100.00 0 -100.00
2020-01-28 2019-12-31 13F WESTERN DIGITAL COM 958102105 6,587 -8 -0.12 417 5.57 0.0419
2019-10-22 2019-09-30 13F WESTERN DIGITAL COM 958102105 6,595 1,532 30.26 395 63.22 0.0435
2019-07-18 2019-06-30 13F WESTERN DIGITAL COM 958102105 5,063 -1,755 -25.74 242 -26.22 0.0307
2019-05-06 2019-03-31 13F/A-1 WESTERN DIGITAL COM 958102105 6,818 -2,359 -25.71 328 -2.38 0.0446
2019-05-01 2019-03-31 13F WESTERN DIGITAL COM 958102105 13,636 4,459 656
2019-02-13 2018-12-31 13F WESTERN DIGITAL COM 958102105 9,177 1,502 19.57 336 -25.33 0.0528
2018-11-14 2018-09-30 13F WESTERN DIGITAL COM 958102105 7,675 -493 -6.04 450 -28.68 0.0550
2018-08-14 2018-06-30 13F WESTERN DIGITAL COM 958102105 8,168 -1,072 -11.60 631 -26.03 0.0850
2018-05-18 2018-03-31 13F WESTERN DIGITAL COM 958102105 9,240 1,095 13.44 853 30.83 0.1127
2018-02-13 2017-12-31 13F WESTERN DIGITAL COM 958102105 8,145 3,712 83.74 652 69.35 0.0864
2017-11-16 2017-09-30 13F WESTERN DIGITAL COM 958102105 4,433 729 19.68 385 17.74 0.0557
2017-08-15 2017-06-30 13F WESTERN DIGITAL COM 958102105 3,704 -3,649 -49.63 327 -46.13 0.0543
2017-05-15 2017-03-31 13F WESTERN DIGITAL COM 958102105 7,353 -207 -2.74 607 17.86 0.1024
2017-02-13 2016-12-31 13F WESTERN DIGITAL COM 958102105 7,560 -4,792 -38.80 515 -28.97 0.0848
2016-11-14 2016-09-30 13F WESTERN DIGITAL COM 958102105 12,352 486 4.10 725 28.32 0.1212
2016-08-08 2016-06-30 13F WESTERN DIGITAL COM 958102105 11,866 11,866 565 0.0993
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
(%)
2022-05-13 2022-03-31 13F WESTERN DIGITAL COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2022-02-14 2021-12-31 13F WESTERN DIGITAL COM Call 5 2 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.