DIMETRICS
W
Western Digital
WDC · Storage
$513.84
-49.48 (-8.78%)
As of Jul 15, 2026 close
Institutional Ownership — Q1 2026 (filed through May 29)
Institutional Holders
1389
+227 vs Q4 2025
Shares Held
327.4M
-6.7M QoQ
% of Shares Out
29.2%
100.5M held with sole discretion
Value Held
$168.2B
at $513.84 · Jul 15, 2026 close
5%+ Owners
4
via 13G/13D
% of Shares Out counts only shares held with sole investment discretion. Where two managers share discretion, Form 13F requires each to report the full position, so summing every filer exceeds 100% of shares outstanding for widely-held names.
Holder Map
Block size ∝ position · color = QoQ change
Whale Activity — Q1 2026 Filings
Increased440
Decreased478
New position358
Closed131
Institutional Shares Held by Quarter
Holders
Sortable · search holders
Source
% of Shrs Out
Period
BlackRock, Inc.13F
35,769,222
+259,704
+0.7%
$9.7B
10.4%
Mar 31, 2026
FMR LLC13F
31,623,418
-2,170,383
-6.4%
$8.6B
9.2%
Mar 31, 2026
VANGUARD CAPITAL MANAGEMENT LLC13F
22,034,861
+22,034,861
new
$6.0B
6.4%
Mar 31, 2026
JPMORGAN CHASE & CO13F
17,512,148
+3,216,183
+22.5%
$4.4B
5.1%
Mar 31, 2026
VANGUARD PORTFOLIO MANAGEMENT LLC13F
17,172,653
+17,172,653
new
$4.6B
5.0%
Mar 31, 2026
STATE STREET CORP13F
15,465,766
-230,188
-1.5%
$4.2B
4.5%
Mar 31, 2026
Capital World Investors13F
11,880,038
+10,816,431
+1017.0%
$3.2B
3.4%
Mar 31, 2026
GEODE CAPITAL MANAGEMENT, LLC13F
9,477,201
+194,769
+2.1%
$2.6B
2.7%
Mar 31, 2026
BANK OF AMERICA CORP /DE/13F
8,489,612
-3,555,039
-29.5%
$2.3B
2.5%
Mar 31, 2026
MORGAN STANLEY13F
7,939,106
-1,005,556
-11.2%
$2.1B
2.3%
Mar 31, 2026
WCM INVESTMENT MANAGEMENT, LLC13F
6,561,810
-129,399
-1.9%
$1.7B
1.9%
Mar 31, 2026
AMERIPRISE FINANCIAL INC13F
5,762,533
-2,757,892
-32.4%
$1.6B
1.7%
Mar 31, 2026
Invesco Ltd.13F
5,530,864
+75,621
+1.4%
$1.5B
1.6%
Mar 31, 2026
GOLDMAN SACHS GROUP INC13F
5,406,883
+847,170
+18.6%
$1.5B
1.6%
Mar 31, 2026
UBS Group AG13F
4,182,454
-368,367
-8.1%
$1.1B
1.2%
Mar 31, 2026
NORTHERN TRUST CORP13F
3,606,563
-65,392
-1.8%
$975.5M
1.0%
Mar 31, 2026
AQR CAPITAL MANAGEMENT LLC13F
3,459,565
+486,862
+16.4%
$913.0M
1.0%
Mar 31, 2026
Capital Research Global Investors13F
3,309,625
+3,309,625
new
$895.1M
1.0%
Mar 31, 2026
Amundi13F
3,058,867
+659,131
+27.5%
$827.4M
0.9%
Mar 31, 2026
Nuveen, LLC13F
2,959,245
-1,604,231
-35.2%
$800.4M
0.9%
Mar 31, 2026
UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC13F
2,902,748
+93,339
+3.3%
$785.2M
0.8%
Mar 31, 2026
D. E. Shaw & Co., Inc.13F
2,688,230
-3,013,088
-52.8%
$727.1M
0.8%
Mar 31, 2026
FRED ALGER MANAGEMENT, LLC13F
2,659,835
-24,506
-0.9%
$719.5M
0.8%
Mar 31, 2026
PRICE T ROWE ASSOCIATES INC /MD/13F
2,646,484
+34,628
+1.3%
$715.8M
0.8%
Mar 31, 2026
Bank of New York Mellon Corp13F
2,508,752
+435,716
+21.0%
$678.6M
0.7%
Mar 31, 2026
DIMENSIONAL FUND ADVISORS LP13F
2,503,321
-1,062,021
-29.8%
$676.8M
0.7%
Mar 31, 2026
CHARLES SCHWAB INVESTMENT MANAGEMENT INC13F
2,206,941
-59,768
-2.6%
$597.0M
0.6%
Mar 31, 2026
Legal & General Group Plc13F
2,129,170
+95,615
+4.7%
$575.9M
0.6%
Mar 31, 2026
VANGUARD FIDUCIARY TRUST CO13F
1,908,325
+1,908,325
new
$516.2M
0.6%
Mar 31, 2026
DEUTSCHE BANK AG\13F
1,872,796
-358,813
-16.1%
$506.6M
0.5%
Mar 31, 2026
HSBC HOLDINGS PLC13F
1,545,167
+277,382
+21.9%
$417.0M
0.4%
Mar 31, 2026
National Pension Service13F
1,437,962
-253,697
-15.0%
$389.0M
0.4%
Mar 31, 2026
BANK OF MONTREAL /CAN/13F
1,405,042
+373,990
+36.3%
$380.0M
0.4%
Mar 31, 2026
Maple Rock Capital Partners Inc.13F
1,400,434
-981,091
-41.2%
$378.8M
0.4%
Mar 31, 2026
AMF Tjanstepension AB13F
1,373,910
-394,049
-22.3%
$371.6M
0.4%
Mar 31, 2026
Value Aligned Research Advisors, LLC13F
1,295,439
+1,295,439
new
$350.4M
0.4%
Mar 31, 2026
ROYAL BANK OF CANADA13F
1,271,074
-711,979
-35.9%
$343.8M
0.4%
Mar 31, 2026
BNP PARIBAS FINANCIAL MARKETS13F
1,188,956
-209,124
-15.0%
$321.6M
0.3%
Mar 31, 2026
Soroban Capital Partners LP13F
1,146,273
+0
+0.0%
$310.1M
0.3%
Mar 31, 2026
RENAISSANCE TECHNOLOGIES LLC13F
1,146,133
+153,600
+15.5%
$310.0M
0.3%
Mar 31, 2026
BARCLAYS PLC13F
1,050,033
-476,351
-31.2%
$284.0M
0.3%
Mar 31, 2026
WELLS FARGO & COMPANY/MN13F
1,024,545
+158,749
+18.3%
$277.1M
0.3%
Mar 31, 2026
Swiss National Bank13F
1,003,307
+52,500
+5.5%
$271.4M
0.3%
Mar 31, 2026
Robeco Institutional Asset Management B.V.13F
984,685
-392,066
-28.5%
$266.3M
0.3%
Mar 31, 2026
Polar Capital Holdings Plc13F
972,432
+59,240
+6.5%
$263.0M
0.3%
Mar 31, 2026
MARSHALL WACE, LLP13F
931,323
+769,455
+475.4%
$251.9M
0.3%
Mar 31, 2026
NOMURA ASSET MANAGEMENT INTERNATIONAL INC.13F
891,662
-133,785
-13.0%
$241.2M
0.3%
Mar 31, 2026
Castle Hook Partners LP13F
878,939
-446,731
-33.7%
$237.7M
0.3%
Mar 31, 2026
Sumitomo Mitsui Trust Group, Inc.13F
836,666
-50,393
-5.7%
$226.3M
0.2%
Mar 31, 2026
DZ BANK AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main13F
827,668
+412,055
+99.1%
$223.9M
0.2%
Mar 31, 2026
Page 1 of 20
Derivatives Institutional Owners
13F put/call positions · excluded from ownership totals
Type
Period
JANE STREET GROUP, LLCPut
6,809,400
+1,096,300
+19.2%
$1.8B
Mar 31, 2026
SUSQUEHANNA INTERNATIONAL GROUP, LLPPut
4,511,500
+709,900
+18.7%
$1.2B
Mar 31, 2026
WELLS FARGO & COMPANY/MNPut
4,005,700
+200
+0.0%
$1.1B
Mar 31, 2026
SUSQUEHANNA INTERNATIONAL GROUP, LLPCall
4,004,300
+408,800
+11.4%
$1.1B
Mar 31, 2026
CITADEL ADVISORS LLCPut
3,558,200
-1,720,600
-32.6%
$962.5M
Mar 31, 2026
CITADEL ADVISORS LLCCall
2,023,900
-1,533,400
-43.1%
$547.4M
Mar 31, 2026
JANE STREET GROUP, LLCCall
1,364,900
-116,000
-7.8%
$369.2M
Mar 31, 2026
D. E. Shaw & Co., Inc.Put
1,125,200
+293,200
+35.2%
$304.4M
Mar 31, 2026
Walleye Trading LLCCall
876,000
-535,400
-37.9%
$101.7M
Mar 31, 2026
Walleye Trading LLCPut
811,400
-828,100
-50.5%
$219.5M
Mar 31, 2026
UBS Group AGCall
391,294
+163,194
+71.5%
$105.8M
Mar 31, 2026
Squarepoint Ops LLCPut
362,100
-222,700
-38.1%
$97.9M
Mar 31, 2026
Squarepoint Ops LLCCall
309,900
-218,000
-41.3%
$83.8M
Mar 31, 2026
MILLENNIUM MANAGEMENT LLCPut
297,000
+136,700
+85.3%
$80.3M
Mar 31, 2026
GOLDMAN SACHS GROUP INCCall
296,200
+40,900
+16.0%
$80.1M
Mar 31, 2026
Point72 Asset Management, L.P.Put
280,100
-184,900
-39.8%
$75.8M
Mar 31, 2026
GOLDMAN SACHS GROUP INCPut
255,800
-38,500
-13.1%
$69.2M
Mar 31, 2026
Point72 Asset Management, L.P.Call
205,000
-95,200
-31.7%
$55.5M
Mar 31, 2026
Caption Management, LLCPut
200,000
+0
+0.0%
$54.1M
Mar 31, 2026
MILLENNIUM MANAGEMENT LLCCall
159,400
-137,800
-46.4%
$43.1M
Mar 31, 2026
PEAK6 LLCPut
153,300
-93,400
-37.9%
$41.5M
Mar 31, 2026
HSBC HOLDINGS PLCPut
150,100
+0
+0.0%
$40.5M
Mar 31, 2026
PINNBROOK CAPITAL MANAGEMENT LPCall
149,600
+111,600
+293.7%
$40.5M
Mar 31, 2026
Parallax Volatility Advisers, L.P.Call
146,400
-85,300
-36.8%
$39.6M
Mar 31, 2026
CAPITAL FUND MANAGEMENT S.A.Put
128,700
-194,000
-60.1%
$34.8M
Mar 31, 2026
TUDOR INVESTMENT CORP ET ALPut
128,600
-82,800
-39.2%
$34.8M
Mar 31, 2026
D. E. Shaw & Co., Inc.Call
119,300
-242,000
-67.0%
$32.3M
Mar 31, 2026
Cavalier Investments, LLCCall
112,100
+112,100
new
$30.3M
Mar 31, 2026
CAPITAL FUND MANAGEMENT S.A.Call
100,600
-163,200
-61.9%
$27.2M
Mar 31, 2026
UBS Group AGPut
100,500
-186,300
-65.0%
$27.2M
Mar 31, 2026
PEAK6 LLCCall
94,700
-91,900
-49.2%
$25.6M
Mar 31, 2026
SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLCPut
90,000
+90,000
new
$24.3M
Mar 31, 2026
TUDOR INVESTMENT CORP ET ALCall
86,000
-316,600
-78.6%
$23.3M
Mar 31, 2026
Qube Research & Technologies LtdPut
81,500
-112,500
-58.0%
$22.0M
Mar 31, 2026
Alphadyne Asset Management LPPut
77,400
+72,400
+1448.0%
$20.9M
Mar 31, 2026
NOMURA HOLDINGS INCPut
72,000
-381,500
-84.1%
$19.5M
Mar 31, 2026
Qube Research & Technologies LtdCall
63,200
-72,700
-53.5%
$17.1M
Mar 31, 2026
Cavalier Investments, LLCPut
62,100
-17,900
-22.4%
$16.8M
Mar 31, 2026
CITIGROUP INCCall
58,000
-250,000
-81.2%
$15.7M
Mar 31, 2026
Alphadyne Asset Management LPCall
53,600
+43,700
+441.4%
$14.5M
Mar 31, 2026
CAPSTONE INVESTMENT ADVISORS, LLCPut
46,600
-41,400
-47.0%
$12.6M
Mar 31, 2026
Walleye Capital LLCCall
43,100
-34,100
-44.2%
$11.7M
Mar 31, 2026
Invesco Ltd.Call
39,500
-35,500
-47.3%
$10.7M
Mar 31, 2026
Walleye Capital LLCPut
39,200
-67,600
-63.3%
$10.6M
Mar 31, 2026
WELLS FARGO & COMPANY/MNCall
33,000
+0
+0.0%
$8.9M
Mar 31, 2026
B. Riley Wealth Advisors, Inc.Call
30,000
+30,000
new
$75.5K
Mar 31, 2026
Oribel Capital Management, LPPut
28,200
+28,200
new
$7.6M
Mar 31, 2026
MARSHALL WACE, LLPCall
21,900
-4,900
-18.3%
$5.9M
Mar 31, 2026
Balyasny Asset Management L.P.Call
19,100
-12,900
-40.3%
$5.2M
Mar 31, 2026
NOMURA HOLDINGS INCCall
17,900
-655,600
-97.3%
$4.8M
Mar 31, 2026
Page 1 of 2
Ownership Events — 13G / 13D
Event-driven, scanned daily
Vanguard Capital Management crosses 5.0%
Initial Schedule 13G · 25,402,917 shares reported
13GApr 30, 2026
Vanguard Portfolio Management crosses 5.0%
Initial Schedule 13G · 17,217,120 shares reported
13GApr 29, 2026
MANAGED ACCOUNT ADVISORS LLC falls below 5% (from 5.3%)
Schedule 13G/A · position exited
13G/AFeb 10, 2026
FMR LLC reports 10.1% (from 7.0%)
Schedule 13G/A · amendment
13G/AJan 8, 2026
MANAGED ACCOUNT ADVISORS LLC reports 5.3% (from 6.4%)
Schedule 13G/A · amendment
13G/ANov 13, 2025
FMR LLC reports 7.0% (from 9.5%)
Schedule 13G/A · amendment
13G/ANov 5, 2025
MANAGED ACCOUNT ADVISORS LLC crosses 5.0%
Initial Schedule 13G · 22,178,966 shares reported
13GAug 14, 2025
FMR LLC reports 9.5% (from 8.1%)
Schedule 13G/A · amendment
13G/AAug 6, 2025
FMR LLC reports 8.1% (from 6.9%)
Schedule 13G/A · amendment
13G/AMay 12, 2025
JPMORGAN CHASE & CO. reports 5.3% (from 6.7%)
Schedule 13G/A · amendment
13G/AApr 22, 2025
Quarterly holdings from SEC Form 13F-HR structured data sets (filed within 45 days of quarter end); 5%+ ownership events from Schedule 13G/13D filings scanned daily via EDGAR. Each row links to the source filing. Est. Avg Cost is a rolling-average estimate — each quarter's added shares priced at that quarter's 13F value ÷ shares, split-adjusted, with history beginning 2024-Q2; positions with one quarter of history or a data-quality flag show “—”.