T-Mobile US, Inc.
US ˙ NasdaqGS ˙ US8725901040

SecurityTMUS / T-Mobile US, Inc.
InstitutionAssetmark, Inc
Latest Disclosed Ownership38,700 shares
Latest Disclosed Value $ 8,128,132
Assetmark, Inc reports 18.95% increase in ownership of TMUS / T-Mobile US, Inc.

On May 6, 2026 - Assetmark, Inc filed a 13F-HR form disclosing ownership of 38,700 shares of T-Mobile US, Inc. (US:TMUS) valued at $8,128,161 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 23, 2026 disclosing 32,536 shares of T-Mobile US, Inc.. This represents a change in shares of 18.95% during the quarter. The current value of the position is $7,022,115 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)
2026-05-06 2026-03-31 13F T-MOBILE US COM 872590104 38,700 6,164 18.95 8,128 23.04 0.0166
2026-01-23 2025-12-31 13F T-MOBILE US COM 872590104 32,536 -734 -2.21 6,606 -17.05 0.0135
2025-11-06 2025-09-30 13F T-MOBILE US COM 872590104 33,270 241 0.73 7,964 1.21 0.0171
2025-08-04 2025-06-30 13F T-MOBILE US COM 872590104 33,029 5,777 21.20 7,870 8.27 0.0186
2025-05-06 2025-03-31 13F T-MOBILE US COM 872590104 27,252 -11,091 -28.93 7,268 -14.12 0.0200
2025-02-06 2024-12-31 13F T-MOBILE US COM 872590104 38,343 -2,486 -6.09 8,463 0.45 0.0230
2024-11-01 2024-09-30 13F T-MOBILE US COM 872590104 40,829 1,721 4.40 8,426 22.30 0.0241
2024-08-13 2024-06-30 13F T-MOBILE US COM 872590104 39,108 1,890 5.08 6,890 13.42 0.0213
2024-05-07 2024-03-31 13F T-MOBILE US COM 872590104 37,218 8,324 28.81 6,075 31.13 0.0197
2024-02-09 2023-12-31 13F T-MOBILE US COM 872590104 28,894 7,000 31.97 4,633 51.08 0.0167
2023-10-27 2023-09-30 13F T-MOBILE US COM 872590104 21,894 7,901 56.46 3,066 57.80 0.0123
2023-08-11 2023-06-30 13F T-MOBILE US INC COM COM 872590104 13,993 1,392 11.05 1,944 6.47 0.0076
2023-05-05 2023-03-31 13F T-MOBILE US INC COM COM 872590104 12,601 926 7.93 1,825 11.69 0.0075
2023-02-10 2022-12-31 13F T-MOBILE US COM 872590104 11,675 2,873 32.64 1,634 38.36 0.0071
2022-11-01 2022-09-30 13F T-MOBILE US COM 872590104 8,802 1,850 26.61 1,181 26.31 0.0055
2022-08-03 2022-06-30 13F T-MOBILE US INC COM COM 872590104 6,952 3,599 107.34 935 117.44 0.0042
2022-05-13 2022-03-31 13F T-MOBILE US INC COM COM 872590104 3,353 1,944 137.97 430 163.80 0.0018
2022-02-14 2021-12-31 13F T-MOBILE US INC COM COM 872590104 1,409 946 204.32 163 176.27 0.0007
2021-11-12 2021-09-30 13F T-MOBILE US INC COM COM 872590104 463 -34 -6.84 59 -18.06 0.0003
2021-08-16 2021-06-30 13F T-MOBILE US INC COM COM 872590104 497 39 8.52 72 26.32 0.0003
2021-05-14 2021-03-31 13F T-MOBILE US COM 872590104 458 201 78.21 57 62.86 0.0003
2021-02-10 2020-12-31 13F T-MOBILE US INC COM COM 872590104 257 148 135.78 35 191.67 0.0002
2020-11-13 2020-09-30 13F T-MOBILE US INC COM COM 872590104 109 102 1,457.14 12 1,100.00 0.0001
2020-08-11 2020-06-30 13F T-MOBILE US INC COM COM 872590104 7 -159 -95.78 1 -92.86 0.0000
2020-05-12 2020-03-31 13F T MOBILE US INC COM COM 872590104 166 166 14 0.0001
2019-08-14 2019-06-30 13F T MOBILE US INC COM COM 872590104 0 -215 -100.00 0 -100.00
2019-05-14 2019-03-31 13F T MOBILE US INC COM COM 872590104 215 -9 -4.02 15 7.14 0.0001
2019-02-13 2018-12-31 13F T MOBILE US INC COM COM 872590104 224 -5 -2.18 14 -12.50 0.0001
2018-11-13 2018-09-30 13F T MOBILE US INC COM COM 872590104 229 229 16 0.0001
2018-05-16 2018-03-31 13F T MOBILE US INC COM COM 872590104 0 -56 -100.00 0 -100.00
2018-02-13 2017-12-31 13F T MOBILE US INC COM COM 872590104 56 40 250.00 4 300.00 0.0000
2017-11-08 2017-09-30 13F T MOBILE US INC COM COM 872590104 16 16 1 0.0000
2017-09-15 2017-03-31 13F/A-1 T MOBILE US INC COM COM 872590104 0 -383 -100.00 0 -100.00
2017-09-15 2016-12-31 13F/A-1 T MOBILE US INC COM COM 872590104 383 383 22 0.0003
2017-02-14 2016-12-31 13F T MOBILE US INC COM COM 872590104 383 22 0.0003
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.