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ATI · Ati Inc

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$215.23 +5.42 (+2.58%) At close · Aug 25
Market Cap
$28.80B
Shares
136.17M

Institutional ownership from SEC Form 13F filings. Investment managers with more than $100 million in U.S. equities must disclose their positions every quarter, within 45 days of quarter-end, so the holdings shown can lag the market by up to a quarter.

Holders: 789
Total Value: $25,382,101,548
Total Shares: 128,777,993

Institutional Ownership Trend

26 quarters

Holder Concentration

Across 789 13F filers · Δ vs Mar 31, 2026
Top Holder
14.5%
Sep 2023 → Jun 2026 · range 11.7% – 15.0%
+1.8 pts
Top 5
32.3%
Sep 2023 → Jun 2026 · range 31.4% – 45.8%
+0.9 pts
Top 10
47.8%
Sep 2023 → Jun 2026 · range 47.8% – 60.8%
−1.8 pts
HHI
373
Sep 2023 → Jun 2026 · range 353 – 568
Broadly held+19

Quarterly Activity

vs Mar 31, 2026
New
177
Increased
302
Decreased
222
Sold Out
65
Unchanged
88
Holder count: +112
Institutional value: +35.5%
Shares held: -0.0%

Top Buyers

vs Mar 31, 2026
Institution Added Now Holds Open

Top Sellers

vs Mar 31, 2026
Institution Sold Now Holds Open

Top New Positions

vs Mar 31, 2026
Institution Acquired Value (USD) Open

Top Sold-Out Positions

vs Mar 31, 2026
Institution Previously Held Last Value (USD) Open
Showing 100 of 821
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Holder Value (USD) % of 13F Shares Open
Key facts CIK 1018963 CUSIP 01741R102 13F (30d) 620 filings 616 filers Visit website Investor relations