Western Digital Corporation
CH ˙ BRSE ˙ US9581021055
DETTE SYMBOL ER IKKE LÆNGERE AKTIVT
SecurityCH:12355 / Western Digital Corporation
InstitutionNissay Asset Management Corp /japan/ /adv
Latest Disclosed Ownership97,121 shares
Latest Disclosed Value $ 26,270,259
Nissay Asset Management Corp /japan/ /adv reports 2.04% increase in ownership of 12355 / Western Digital Corporation

On May 15, 2026 - Nissay Asset Management Corp /japan/ /adv filed a 13F-HR form disclosing ownership of 97,121 shares of Western Digital Corporation (CH:12355) valued at $26,270,259 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 95,175 shares of Western Digital Corporation. This represents a change in shares of 2.04% during the quarter.

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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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 97,121 1,946 2.04 26,270 60.23 0.1392
2026-02-17 2025-12-31 13F WESTERN DIGITAL COM 958102105 95,175 49,256 107.27 16,396 197.39 0.0853
2025-11-14 2025-09-30 13F WESTERN DIGITAL COM 958102105 45,919 1,139 2.54 5,513 92.43 0.0304
2025-08-14 2025-06-30 13F WESTERN DIGITAL COM 958102105 44,780 1,721 4.00 2,865 64.66 0.0168
2025-05-15 2025-03-31 13F WESTERN DIGITAL COM 958102105 43,059 529 1.24 1,741 -32.58 0.0113
2025-02-14 2024-12-31 13F WESTERN DIGITAL COM 958102105 42,530 2,595 6.50 2,582 -5.35 0.0157
2024-11-14 2024-09-30 13F WESTERN DIGITAL COM 958102105 39,935 1,195 3.08 2,727 -7.09 0.0173
2024-08-14 2024-06-30 13F WESTERN DIGITAL COM 958102105 38,740 1,761 4.76 2,935 16.33 0.0194
2024-05-15 2024-03-31 13F WESTERN DIGITAL COM 958102105 36,979 699 1.93 2,523 32.86 0.0175
2024-02-14 2023-12-31 13F WESTERN DIGITAL COM 958102105 36,280 913 2.58 1,900 17.73 0.0153
2023-11-14 2023-09-30 13F WESTERN DIGITAL COM 958102105 35,367 1,121 3.27 1,614 24.27 0.0143
2023-08-14 2023-06-30 13F WESTERN DIGITAL COM 958102105 34,246 -526 -1.51 1,299 -0.84 0.0112
2023-05-15 2023-03-31 13F WESTERN DIGITAL COM 958102105 34,772 -874 -2.45 1,310 16.46 0.0117
2023-02-14 2022-12-31 13F WESTERN DIGITAL COM 958102105 35,646 -1,283 -3.47 1,125 -6.49 0.0107
2022-11-14 2022-09-30 13F WESTERN DIGITAL COM 958102105 36,929 1,211 3.39 1,202 -24.92 0.0126
2022-08-15 2022-06-30 13F WESTERN DIGITAL COM 958102105 35,718 -111 -0.31 1,601 -10.01 0.0159
2022-05-16 2022-03-31 13F WESTERN DIGITAL COM 958102105 35,829 1,015 2.92 1,779 -21.63 0.0155
2022-02-14 2021-12-31 13F WESTERN DIGITAL COM 958102105 34,814 2,196 6.73 2,270 23.30 0.0174
2021-11-10 2021-09-30 13F WESTERN DIGITAL COM 958102105 32,618 -1,388 -4.08 1,841 -23.93 0.0156
2021-08-13 2021-06-30 13F WESTERN DIGITAL COM 958102105 34,006 -2,830 -7.68 2,420 -1.59 0.0212
2021-05-11 2021-03-31 13F WESTERN DIGITAL COM 958102105 36,836 -580 -1.55 2,459 18.68 0.0242
2021-02-08 2020-12-31 13F WESTERN DIGITAL COM 958102105 37,416 150 0.40 2,072 52.13 0.0312
2020-10-20 2020-09-30 13F WESTERN DIGITAL COM 958102105 37,266 -7,837 -17.38 1,362 -31.59 0.0230
2020-07-27 2020-06-30 13F WESTERN DIGITAL COM 958102105 45,103 1,489 3.41 1,991 9.70 0.0386
2020-05-05 2020-03-31 13F WESTERN DIGITAL COM 958102105 43,614 13,888 46.72 1,815 -3.82 0.0462
2020-02-14 2019-12-31 13F WESTERN DIGITAL COM 958102105 29,726 -1,420 -4.56 1,887 1.56 0.0419
2019-11-14 2019-09-30 13F WESTERN DIGITAL COM 958102105 31,146 1,353 4.54 1,858 31.12 0.0460
2019-08-07 2019-06-30 13F WESTERN DIGITAL COM 958102105 29,793 -15,346 -34.00 1,417 -34.67 0.0358
2019-05-03 2019-03-31 13F WESTERN DIGITAL COM 958102105 45,139 -991 -2.15 2,169 27.21 0.0573
2019-02-06 2018-12-31 13F WESTERN DIGITAL COM 958102105 46,130 3,910 9.26 1,705 -31.03 0.0520
2018-10-30 2018-09-30 13F WESTERN DIGITAL COM 958102105 42,220 1,030 2.50 2,472 -22.48 0.0665
2018-08-08 2018-06-30 13F WESTERN DIGITAL COM 958102105 41,190 1,764 4.47 3,189 -12.34 0.0933
2018-05-14 2018-03-31 13F WESTERN DIGITAL COM 958102105 39,426 -207 -0.52 3,638 15.42 0.1137
2018-02-14 2017-12-31 13F WESTERN DIGITAL COM 958102105 39,633 39,633 3,152 0.0960
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.