Mattel, Inc.
AT ˙ WBAG ˙ US5770811025
12,21 € ↓ -0,19 (-1,55%)
2026-06-04
DEL PRIS
SecurityAT:MAT / Mattel, Inc.
InstitutionHolocene Advisors, LP
Latest Disclosed Ownership244,739 shares
Latest Disclosed Value $ 3,556,058
Holocene Advisors, LP reports 95.56% increase in ownership of MAT / Mattel, Inc.

On May 15, 2026 - Holocene Advisors, LP filed a 13F-HR form disclosing ownership of 244,739 shares of Mattel, Inc. (AT:MAT) valued at $3,032,316 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 125,148 shares of Mattel, Inc.. This represents a change in shares of 95.56% during the quarter. The current value of the position is $2,987,774 USD.

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 MATTEL COM 577081102 244,739 119,591 95.56 3,556 43.27 0.0086
2026-02-17 2025-12-31 13F MATTEL COM 577081102 125,148 -15,309 -10.90 2,483 5.04 0.0052
2025-11-14 2025-09-30 13F MATTEL COM 577081102 140,457 140,457 2,364 0.0054
2025-02-14 2024-12-31 13F MATTEL COM 577081102 0 -86,809 -100.00 0 -100.00
2024-11-14 2024-09-30 13F MATTEL COM 577081102 86,809 -230,990 -72.68 1,654 -68.01 0.0067
2024-08-14 2024-06-30 13F MATTEL COM 577081102 317,799 60,259 23.40 5,167 1.29 0.0216
2024-05-15 2024-03-31 13F MATTEL COM 577081102 257,540 257,540 5,102 0.0187
2023-11-14 2023-09-30 13F MATTEL COM 577081102 0 -214,379 -100.00 0 -100.00
2023-08-14 2023-06-30 13F MATTEL COM 577081102 214,379 130,134 154.47 4,189 170.19 0.0179
2023-05-15 2023-03-31 13F MATTEL COM 577081102 84,245 35,499 72.82 1,551 78.37 0.0076
2023-02-14 2022-12-31 13F MATTEL COM 577081102 48,746 48,746 870 0.0053
2022-05-16 2022-03-31 13F MATTEL COM 577081102 0 -1,706,810 -100.00 0 -100.00
2022-02-14 2021-12-31 13F MATTEL COM 577081102 1,706,810 267,181 18.56 36,799 37.72 0.1915
2021-11-15 2021-09-30 13F MATTEL COM 577081102 1,439,629 610,891 73.71 26,720 60.40 0.1452
2021-08-16 2021-06-30 13F MATTEL COM 577081102 828,738 -297,043 -26.39 16,658 -25.72 0.0941
2021-05-17 2021-03-31 13F MATTEL COM 577081102 1,125,781 1,125,781 22,426 0.1407
2020-11-16 2020-09-30 13F MATTEL COM 577081102 0 -92,680 -100.00 0 -100.00
2020-08-14 2020-06-30 13F MATTEL COM 577081102 92,680 29,916 47.66 896 62.03 0.0079
2020-05-15 2020-03-31 13F MATTEL COM 577081102 62,764 62,764 553 0.0059
2020-02-14 2019-12-31 13F MATTEL COM 577081102 0 -229,583 -100.00 0 -100.00
2019-11-14 2019-09-30 13F MATTEL COM 577081102 229,583 229,583 2,615 0.0269
2018-11-14 2018-09-30 13F MATTEL COM 577081102 0 -993,013 -100.00 0 -100.00
2018-08-14 2018-06-30 13F MATTEL COM 577081102 993,013 973,988 5,119.52 16,305 6,422.00 0.3469
2018-05-15 2018-03-31 13F MATTEL COM 577081102 19,025 -925,253 -97.99 250 -98.28 0.0057
2018-02-14 2017-12-31 13F MATTEL COM 577081102 944,278 944,278 14,523 0.3680
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.