ATI Inc.
MX ˙ BMV ˙ US01741R1023
SecurityMX:ATI / ATI Inc.
InstitutionCerity Partners LLC
Latest Disclosed Ownership41,648 shares
Latest Disclosed Value $ 6,058,118
Cerity Partners LLC reports 22.56% increase in ownership of ATI / ATI Inc.

On May 15, 2026 - Cerity Partners LLC filed a 13F-HR form disclosing ownership of 41,648 shares of ATI Inc. (MX:ATI) valued at $6,058,118 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 33,983 shares of ATI Inc.. This represents a change in shares of 22.56% 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 ATI COM 01741R102 41,648 7,665 22.56 6,058 55.37 0.0043
2026-02-11 2025-12-31 13F ATI COM 01741R102 33,983 27,911 459.67 3,900 690.87 0.0057
2025-10-22 2025-09-30 13F ATI COM 01741R102 6,072 2,825 87.00 494 76.07 0.0008
2025-08-13 2025-06-30 13F ATI Stock 01741R102 3,247 -6,306 -66.01 280 -43.66 0.0005
2025-04-30 2025-03-31 13F ATI Stock 01741R102 9,553 -579 -5.71 497 -24.70 0.0010
2025-02-13 2024-12-31 13F ATI COM 01741R102 10,132 -4,939 -32.77 661 -34.52 0.0014
2024-11-12 2024-09-30 13F ATI Stock 01741R102 15,071 9,027 149.35 1,008 200.90 0.0022
2024-08-13 2024-06-30 13F ATI COM 01741R102 6,044 -4,985 -45.20 335 -40.60 0.0009
2024-05-14 2024-03-31 13F ATI Stock 01741R102 11,029 11,029 564 0.0015
2023-08-14 2023-06-30 13F ATI Equities 01741R102 0 -6,776 -100.00 0 -100.00
2023-05-11 2023-03-31 13F ATI Equities 01741R102 6,776 6,776 1,341 0.0032
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.