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NASDAQ · Technology · Holders

Seagate Technology (STX) Institutional Ownership & Insider Trading History

Top STX institutional shareholders, filing changes, and Form 4 insider activity with filters for buys, sales, option exercises, gifts, and tax withholding.

Section freshness

Prices as of Sep 28, 4:00 PM EDT · Fundamentals checked Sep 29, 8:35 AM EDT · Statements Jul 3, 2026

Ownership read

STX insider transaction activity: Net selling.

Blackrock Inc. is the largest institutional holder. 62 sales and 0 purchases appear in the recent Form 4 filings. Use the filters below to separate open-market activity from option exercises, gifts, awards, and tax withholding.

Review insider tradesView institutions

Insider flow

STX

Purchases0
Sales680.09K

Directional bars ignore awards, gifts, conversions, and tax withholding rows.

Top holder

15.17M

Blackrock Inc.

Insider transaction activity

Net selling

$515.42M sold / $0.0000 bought

Observations shown

130

10 holder / 120 insider

Holder rows
10
Yahoo Finance · Filing dates shown per row
Increased / initiated
6
4 decreased · provider-reported changes
Insider rows
120
Yahoo Finance · Filing dates shown per row

Ownership concentration and transaction activity

Top 10 reported holders
36.86% outstanding
Changes with share-count history
Prior-position data unavailable
New / exited positions
0 / 0 explicitly reported
Largest increase with share-count history
Prior share counts unavailable

Reported-holder cohort only; absence from a limited provider list does not establish an exit. Changes are provider-reported and are only comparable quarter over quarter when the position periods match.

Net shares sold: 680,094

Sale-code S shares minus purchase-code P shares in this sample. Includes disclosed plans and unknown plan status; excludes grants, gifts, exercises and withholding. This is activity, not sentiment.

  • Purchase / sale; plan unknown: 62
  • Conversion / exercise: 12
  • Other / unclassified: 46

Top 10 institutional holders

Seagate Technology (STX) institutional ownership

Ranked by reported share count, with position changes and separate position and filing dates where ownership data supplies them.

Seagate Technology (STX) institutional ownership
#Institution% heldSharesChange %Position / filing date
1
Blackrock Inc.
6.67%15.17M+6.25%Position as of Jun 30, 2026Filing date unknown
2
Vanguard Capital Management LLC
6.43%14.63M+3.35%Position as of Jun 30, 2026Filing date unknown
3
State Street Corporation
4.36%9.91M+6.33%Position as of Jun 30, 2026Filing date unknown
4
FMR, LLC
3.59%8.15M-0.29%Position as of Jun 30, 2026Filing date unknown
5
Vanguard Portfolio Management LLC
3.52%8.00M-27.90%Position as of Jun 30, 2026Filing date unknown
6
Invesco Ltd.
3.31%7.54M+5.02%Position as of Jun 30, 2026Filing date unknown
7
WCM Investment Management, LLC
2.34%5.32M+22.40%Position as of Jun 30, 2026Filing date unknown
8
JPMORGAN CHASE & CO
2.29%5.20M-21.90%Position as of Jun 30, 2026Filing date unknown
9
Geode Capital Management, LLC
2.27%5.16M+1.87%Position as of Jun 30, 2026Filing date unknown
10
Morgan Stanley
2.08%4.72M-0.81%Position as of Jun 30, 2026Filing date unknown
Showing 10 of 10 matching institutional rows.

Recent insider transactions

Seagate Technology (STX) Form 4 filings

Action codes are translated so open-market buys and sales are separate from awards, gifts, conversions, and tax withholding.

Seagate Technology (STX) Form 4 insider transactions
#Insider% companyActionSharesTransaction date
1
MORRIS JOHN CHRISTOPHER
Chief Technology Officer
<0.01%SaleOpen-market or direct sale reported on Form 4.
Transaction context
Classification:
Purchase / sale; plan unknown
10b5-1:
Unknown; not supplied by provider
Holdings after:
Not reported
Position sold:
Not calculable
Filed:
Not reported

Position sold = shares sold ÷ (shares sold + holdings after). Separate accounts or security classes may not represent total beneficial ownership.

9.35KSep 21, 2026
2
MORRIS JOHN CHRISTOPHER
Chief Technology Officer
<0.01%Conversion of Exercise of derivative securityProvider-supplied Form 4 action code. Review the original filing before making a trading judgment.
Transaction context
Classification:
Conversion / exercise
10b5-1:
Unknown; not supplied by provider
Holdings after:
Not reported
Position sold:
Not calculable
Filed:
Not reported

Position sold = shares sold ÷ (shares sold + holdings after). Separate accounts or security classes may not represent total beneficial ownership.

915Sep 21, 2026
3
MORRIS JOHN CHRISTOPHER
Chief Technology Officer
<0.01%SaleOpen-market or direct sale reported on Form 4.
Transaction context
Classification:
Purchase / sale; plan unknown
10b5-1:
Unknown; not supplied by provider
Holdings after:
Not reported
Position sold:
Not calculable
Filed:
Not reported

Position sold = shares sold ÷ (shares sold + holdings after). Separate accounts or security classes may not represent total beneficial ownership.

15.46KSep 15, 2026
4
MOSLEY WILLIAM D
Chief Executive Officer
0.04%SaleOpen-market or direct sale reported on Form 4.
Transaction context
Classification:
Purchase / sale; plan unknown
10b5-1:
Unknown; not supplied by provider
Holdings after:
Not reported
Position sold:
Not calculable
Filed:
Not reported

Position sold = shares sold ÷ (shares sold + holdings after). Separate accounts or security classes may not represent total beneficial ownership.

97.89KSep 15, 2026
5
TEH BAN-SENG
Officer
0.02%SaleOpen-market or direct sale reported on Form 4.
Transaction context
Classification:
Purchase / sale; plan unknown
10b5-1:
Unknown; not supplied by provider
Holdings after:
Not reported
Position sold:
Not calculable
Filed:
Not reported

Position sold = shares sold ÷ (shares sold + holdings after). Separate accounts or security classes may not represent total beneficial ownership.

52.73KSep 15, 2026
6
ROMANO GIANLUCA
Chief Financial Officer
0.02%SaleOpen-market or direct sale reported on Form 4.
Transaction context
Classification:
Purchase / sale; plan unknown
10b5-1:
Unknown; not supplied by provider
Holdings after:
Not reported
Position sold:
Not calculable
Filed:
Not reported

Position sold = shares sold ÷ (shares sold + holdings after). Separate accounts or security classes may not represent total beneficial ownership.

49.98KSep 15, 2026
7
MORRIS JOHN CHRISTOPHER
Chief Technology Officer
<0.01%SaleOpen-market or direct sale reported on Form 4.
Transaction context
Classification:
Purchase / sale; plan unknown
10b5-1:
Unknown; not supplied by provider
Holdings after:
Not reported
Position sold:
Not calculable
Filed:
Not reported

Position sold = shares sold ÷ (shares sold + holdings after). Separate accounts or security classes may not represent total beneficial ownership.

492Sep 14, 2026
8
MOSLEY WILLIAM D
Chief Executive Officer
<0.01%SaleOpen-market or direct sale reported on Form 4.
Transaction context
Classification:
Purchase / sale; plan unknown
10b5-1:
Unknown; not supplied by provider
Holdings after:
Not reported
Position sold:
Not calculable
Filed:
Not reported

Position sold = shares sold ÷ (shares sold + holdings after). Separate accounts or security classes may not represent total beneficial ownership.

1.87KSep 14, 2026
9
TEH BAN-SENG
Officer
<0.01%SaleOpen-market or direct sale reported on Form 4.
Transaction context
Classification:
Purchase / sale; plan unknown
10b5-1:
Unknown; not supplied by provider
Holdings after:
Not reported
Position sold:
Not calculable
Filed:
Not reported

Position sold = shares sold ÷ (shares sold + holdings after). Separate accounts or security classes may not represent total beneficial ownership.

989Sep 14, 2026
10
ROMANO GIANLUCA
Chief Financial Officer
<0.01%SaleOpen-market or direct sale reported on Form 4.
Transaction context
Classification:
Purchase / sale; plan unknown
10b5-1:
Unknown; not supplied by provider
Holdings after:
Not reported
Position sold:
Not calculable
Filed:
Not reported

Position sold = shares sold ÷ (shares sold + holdings after). Separate accounts or security classes may not represent total beneficial ownership.

5.55KSep 14, 2026
11
MORRIS JOHN CHRISTOPHER
Chief Technology Officer
0.01%OtherProvider-supplied Form 4 action code. Review the original filing before making a trading judgment.
Transaction context
Classification:
Other / unclassified
10b5-1:
Unknown; not supplied by provider
Holdings after:
Not reported
Position sold:
Not calculable
Filed:
Not reported

Position sold = shares sold ÷ (shares sold + holdings after). Separate accounts or security classes may not represent total beneficial ownership.

30.13KSep 14, 2026
12
MOSLEY WILLIAM D
Chief Executive Officer
0.08%OtherProvider-supplied Form 4 action code. Review the original filing before making a trading judgment.
Transaction context
Classification:
Other / unclassified
10b5-1:
Unknown; not supplied by provider
Holdings after:
Not reported
Position sold:
Not calculable
Filed:
Not reported

Position sold = shares sold ÷ (shares sold + holdings after). Separate accounts or security classes may not represent total beneficial ownership.

177.00KSep 14, 2026
Showing 12 of 120 matching Form 4 rows. Percent of company uses current shares outstanding.

Frequently asked

Common questions.

Who are the largest STX shareholders?

Blackrock Inc. is the largest reported institutional holder of STX, with 15.17 million shares, or about 6.67% of shares outstanding.

What does the institutional filing activity show for STX?

Seagate Technology has 10 institutional rows on file: 6 increased or initiated positions and 4 reduced them.

What insider transactions are available for STX?

TECHi shows 120 dated STX insider transactions through Sep 21, 2026, with transaction types kept separate so administrative actions are not presented as open-market trades.

Are STX insiders buying or selling?

The displayed STX activity reads Net selling: 62 sales and 0 purchases. Other transaction types remain separate.

Who is the most active reported STX insider?

MOSLEY WILLIAM D has the largest absolute share movement in the displayed STX filing rows, totaling 678,194 shares. The action labels provide the transaction context.

All data sources

Search the dated figures used for this view. Each entry identifies its units, reporting period and calculation status.

How to use this page

Use this to check who owns the float and whether insiders are active.

Best for Institutional concentration, insider transaction pattern, and float context.

Weak when Filings are delayed or transactions are administrative rather than economic.

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