Western Digital Corporation
CH ˙ BRSE ˙ US9581021055
DETTE SYMBOL ER IKKE LÆNGERE AKTIVT
SecurityCH:12355 / Western Digital Corporation
InstitutionCibc World Markets Corp
Latest Disclosed Ownership88,744 shares
Latest Disclosed Value $ 15,287,929
Cibc World Markets Corp ownership in 12355 / Western Digital Corporation

On February 12, 2026 - Cibc World Markets Corp filed a 13F-HR form disclosing ownership of 88,744 shares of Western Digital Corporation (CH:12355) valued at $15,287,929 USD as of December 31, 2025. The entity filed a previous 13F-HR on August 14, 2025 disclosing 43,768 shares of Western Digital Corporation. This represents a change in shares of 102.76% during the quarter.

Cibc World Markets Corp has a history of taking positions in derivatives of the underlying security (12355) in the form of stock options. The firm currently holds call options representing 0 of underlying shares valued at $0 USD and put 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.

CH:12355 / 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)
2026-02-12 2025-12-31 13F WESTERN DIGITAL COM 958102105 88,744 44,976 102.76 15,288 445.96 0.0736
2025-08-14 2025-06-30 13F WESTERN DIGITAL COM 958102105 43,768 1,909 4.56 2,801 65.48 0.0176
2025-05-13 2025-03-31 13F WESTERN DIGITAL COM 958102105 41,859 -12,671 -23.24 1,692 -47.95 0.0133
2025-02-10 2024-12-31 13F WESTERN DIGITAL COM 958102105 54,530 10,251 23.15 3,252 7.54 0.0190
2024-11-13 2024-09-30 13F WESTERN DIGITAL COM 958102105 44,279 2,185 5.19 3,024 -5.21 0.0218
2024-08-12 2024-06-30 13F WESTERN DIGITAL COM 958102105 42,094 9,595 29.52 3,189 43.84 0.0209
2024-05-13 2024-03-31 13F WESTERN DIGITAL COM 958102105 32,499 -9,228 -22.12 2,218 1.46 0.0145
2024-02-13 2023-12-31 13F WESTERN DIGITAL COM COM 958102105 41,727 24,068 136.29 2,185 171.43 0.0119
2023-11-13 2023-09-30 13F WESTERN DIGITAL COM 958102105 17,659 -19,839 -52.91 806 -43.39 0.0079
2023-08-04 2023-06-30 13F WESTERN DIGITAL COM 958102105 37,498 2,712 7.80 1,422 8.55 0.0115
2023-05-11 2023-03-31 13F WESTERN DIGITAL COM COM 958102105 34,786 -2,152,174 -98.41 1,310 -98.10 0.0214
2023-02-09 2022-12-31 13F WESTERN DIGITAL COM 958102105 2,186,960 2,157,836 7,409.13 68,999 7,178.27 0.4645
2022-11-14 2022-09-30 13F WESTERN DIGITAL COM 958102105 29,124 -12,890 -30.68 948 -49.65 0.0132
2022-08-12 2022-06-30 13F WESTERN DIGITAL COM 958102105 42,014 22,994 120.89 1,883 99.47 0.0177
2022-05-13 2022-03-31 13F WESTERN DIGITAL COM 958102105 19,020 19,020 944 0.0074
2022-02-11 2021-12-31 13F WESTERN DIGITAL COM 958102105 0 -17,276 -100.00 0 -100.00
2021-11-12 2021-09-30 13F WESTERN DIGITAL COM 958102105 17,276 -169,986 -90.77 975 -92.68 0.0066
2021-08-10 2021-06-30 13F WESTERN DIGITAL COM 958102105 187,262 133,447 247.97 13,327 271.02 0.0927
2021-05-07 2021-03-31 13F WESTERN DIGITAL COM 958102105 53,815 -2,245 -4.00 3,592 15.68 0.0224
2021-02-12 2020-12-31 13F WESTERN DIGITAL COM 958102105 56,060 2,784 5.23 3,105 59.48 0.0156
2020-11-12 2020-09-30 13F WESTERN DIGITAL COM 958102105 53,276 -22,297 -29.50 1,947 -41.65 0.0190
2020-08-12 2020-06-30 13F WESTERN DIGITAL COM 958102105 75,573 -522 -0.69 3,337 5.37 0.0358
2020-05-12 2020-03-31 13F WESTERN DIGITAL COM 958102105 76,095 -26,075 -25.52 3,167 -51.16 0.0405
2020-02-13 2019-12-31 13F WESTERN DIGITAL COM 958102105 102,170 22,533 28.29 6,485 36.53 0.0420
2019-11-12 2019-09-30 13F WESTERN DIGITAL COM 958102105 79,637 -5,581 -6.55 4,750 17.23 0.0443
2019-08-13 2019-06-30 13F WESTERN DIGITAL COM 958102105 85,218 14,718 20.88 4,052 19.60 0.0312
2019-05-14 2019-03-31 13F WESTERN DIGITAL COM 958102105 70,500 -1,214 -1.69 3,388 27.80 0.0277
2019-02-13 2018-12-31 13F/A-1 WESTERN DIGITAL COM 958102105 71,714 2,875 4.18 2,651 -34.22 0.0247
2019-02-13 2018-12-31 13F WESTERN DIGITAL COM 958102105 71,714 2,875 2,651
2018-11-13 2018-09-30 13F WESTERN DIGITAL COM 958102105 68,839 14,708 27.17 4,030 -3.82 0.0344
2018-08-13 2018-06-30 13F WESTERN DIGITAL COM 958102105 54,131 -92,805 -63.16 4,190 -69.10 0.0362
2018-05-11 2018-03-31 13F WESTERN DIGITAL COM 958102105 146,936 -424,320 -74.28 13,558 -70.16 0.1442
2018-02-13 2017-12-31 13F WESTERN DIGITAL COM 958102105 571,256 18,927 3.43 45,432 -4.80 0.3263
2017-11-14 2017-09-30 13F WESTERN DIGITAL COM 958102105 552,329 322,252 140.06 47,721 134.10 0.4578
2017-08-11 2017-06-30 13F WESTERN DIGITAL COM 958102105 230,077 198,504 628.71 20,385 682.23 0.2156
2017-05-10 2017-03-31 13F WESTERN DIGITAL COM 958102105 31,573 10,545 50.15 2,606 82.37 0.0212
2017-02-13 2016-12-31 13F WESTERN DIGITAL COM 958102105 21,028 -12,438 -37.17 1,429 -26.98 0.0146
2016-11-14 2016-09-30 13F WESTERN DIGITAL COM 958102105 33,466 14,209 73.79 1,957 115.05 0.0372
2016-08-11 2016-06-30 13F WESTERN DIGITAL COM 958102105 19,257 5,300 37.97 910 38.09 0.0236
2016-05-12 2016-03-31 13F WESTERN DIGITAL COM 958102105 13,957 -5,256 -27.36 659 -42.89 0.0145
2016-02-10 2015-12-31 13F WESTERN DIGITAL COM 958102105 19,213 3,270 20.51 1,154 -8.92 0.0235
2015-11-16 2015-09-30 13F WESTERN DIGITAL COM 958102105 15,943 9,308 140.29 1,267 143.65 0.0342
2015-08-14 2015-06-30 13F/A-1 WESTERN DIGITAL COM 958102105 6,635 0 520 0.0021
2015-08-19 2015-06-30 13F/A-2 WESTERN DIGITAL COM 958102105 6,635 0 520 0.0022
2015-11-20 2015-06-30 13F/A-3 WESTERN DIGITAL COM 958102105 6,635 6,635 520 0.0164
2015-08-13 2015-06-30 13F WESTERN DIGITAL COM 958102105 6,635 520 0.0022
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
(%)
2017-02-13 2016-12-31 13F WESTERN DIGITAL CORP CALL COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2016-11-14 2016-09-30 13F WESTERN DIGITAL CORP CALL COM Call 333,000 566.00 19,471 394.31 n/a n/a n/a
2016-08-11 2016-06-30 13F WESTERN DIGITAL CORP CALL COM Call 50,000 3,939 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
(%)
2017-02-13 2016-12-31 13F WESTERN DIGITAL CORP PUT COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2016-11-14 2016-09-30 13F WESTERN DIGITAL CORP PUT COM Put 333,000 566.00 19,471 394.31 n/a n/a n/a
2016-08-11 2016-06-30 13F WESTERN DIGITAL CORP PUT COM Put 50,000 3,939 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.