Whale Analyzer
STX Institutional Holders and 13F Ownership
Compare 9 tracked holders of STX, their reported positions and disclosed changes. Coverage is limited to the investors tracked by Whale Analyzer; these records do not establish all shareholders or current trades. Capital Group is the largest reported holder at $4.18B; the top five funds control 95.7% of reported ownership; institutions were net buying last quarter (7 increased, 2 reduced); the stock trades above the aggregate whale cost basis of $433.65. Top tracked holders include Capital Group, Stephen Mandel, NPS Korea, and Chase Coleman.
Continue to the live STX dashboardTop holders
| Investor | Reported value | Shares | Change | Report date |
|---|---|---|---|---|
| Capital Group 13F portfolio Capital Research Global Investors holdings | $4.18B | 4.3M | Reduced | 2026-06-30 |
| Stephen Mandel 13F portfolio Lone Pine Capital holdings | $965.1M | 1.0M | New | 2026-06-30 |
| NPS Korea 13F portfolio National Pension Service holdings | $805.5M | 834.7K | Increased | 2026-06-30 |
| Chase Coleman 13F portfolio Tiger Global Management holdings | $275.1M | 285.1K | New | 2026-06-30 |
| Ray Dalio 13F portfolio Bridgewater Associates holdings | $192.8M | 199.8K | Reduced | 2026-06-30 |
| Whale Rock Capital 13F portfolio Whale Rock Capital Management holdings | $143.3M | 148.5K | New | 2026-06-30 |
| Stanley Druckenmiller 13F portfolio Duquesne Family Office holdings | $117.7M | 122.0K | Increased | 2026-06-30 |
| Dan Sundheim 13F portfolio D1 Capital Partners holdings | $29.1M | 30.1K | New | 2026-06-30 |
| Lee Ainslie 13F portfolio Maverick Capital holdings | $1.2M | 1.2K | New | 2026-06-30 |
Ownership concentration
Reported ownership of STX is highly concentrated across tracked institutions.
- Single largest holder: 62.3% of reported ownership
- Top 5 holders: 95.7%
- Top 10 holders: 100.0%
Whale activity this quarter
Across 9 tracked institutions, 7 increased, 2 reduced. Net positioning is net buying.
- Capital Group — Capital Research Global Investors ($4.18B) (▼ 24.6% qoq shares)
- Stephen Mandel — Lone Pine Capital ($965.1M) · avg cost $579.03
- NPS Korea — National Pension Service ($805.5M) (▲ 0.8% qoq shares) · avg cost $178.69
- Chase Coleman — Tiger Global Management ($275.1M) · avg cost $579.03
- Ray Dalio — Bridgewater Associates ($192.8M) (▼ 39.3% qoq shares)
- Whale Rock Capital — Whale Rock Capital Management ($143.3M) · avg cost $579.03
- Stanley Druckenmiller — Duquesne Family Office ($117.7M) (▲ 140.6% qoq shares)
- Dan Sundheim — D1 Capital Partners ($29.1M) · avg cost $579.03
Whale cost basis vs current price
The aggregate tracked cost basis is $433.65 versus a current price of $830.17, so STX trades above its cost basis (+91.4%). Average unrealized P&L across tracked holders: 119%.
Sector positioning — Information Technology
STX sits within the Information Technology sector alongside 135 other tracked names. Compare whale ownership across peers:
How to use this page
Values are reported public positions from tracked 13F filers and disclosures — not real-time ownership totals. Open the live STX dashboard for price charts and cross-investor scans, or read the SEC 13F guide.
Related stock holder pages
- AVGO whale holders — BROADCOM INC
- NVDA whale holders — NVIDIA CORPORATION
- MSFT whale holders — MICROSOFT CORP
- AMZN whale holders — AMAZON COM INC
- LLY whale holders — ELI LILLY & CO
- GOOGL whale holders — ALPHABET INC
- META whale holders — META PLATFORMS INC
- AAPL whale holders — APPLE INC
Learn more in Whale Analyzer Academy
Deepen your read on STX with these Whale Analyzer Academy guides:
Frequently asked questions
Who owns STX stock?
Whale Analyzer tracks 9 public institutional holders of STX with a combined reported value of $6.71B. See the holder table above for the largest tracked positions.
Which top funds are buying STX?
Tracked institutions were net buying last quarter — 7 increased, 2 reduced. Check the "Change" column: "New" = fresh position, "Increased" = added, "Reduced" = trimmed.
How concentrated is STX ownership?
The top five tracked holders report 95.7% of aggregate ownership.
Is STX above or below the whale cost basis?
The aggregate tracked cost basis is $433.65 versus a current price of $830.17 (+91.4%).
What does 13F ownership mean for STX?
These are historical reported positions from tracked filers, not real-time ownership or a complete shareholder register. Use the interactive STX dashboard to explore them, or read our 13F Alpha Signals Guide.