T-Mobile US, Inc.
MX ˙ BMV ˙ US8725901040
SecurityMX:TMUS / T-Mobile US, Inc.
InstitutionCookson Peirce & Co Inc
Latest Disclosed Ownership9,191 shares
Latest Disclosed Value $ 1,930,459
Cookson Peirce & Co Inc reports 36.43% increase in ownership of TMUS / T-Mobile US, Inc.

On April 30, 2026 - Cookson Peirce & Co Inc filed a 13F-HR form disclosing ownership of 9,191 shares of T-Mobile US, Inc. (MX:TMUS) valued at $1,930,459 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 6,737 shares of T-Mobile US, Inc.. This represents a change in shares of 36.43% 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)
2026-04-30 2026-03-31 13F T-MOBILE US COM 872590104 9,191 2,454 36.43 1,930 41.19 0.0817
2026-02-11 2025-12-31 13F T-MOBILE US COM 872590104 6,737 6,737 1,368 0.0567
2023-08-01 2023-06-30 13F T-MOBILE US CS 872590104 0 -321,813 -100.00 0 -100.00
2023-05-03 2023-03-31 13F T-MOBILE US CS 872590104 321,813 3,810 1.20 47 4.55 2.9865
2023-01-31 2022-12-31 13F T-MOBILE US CS 872590104 318,003 10,492 3.41 45 -99.89 2.8946
2022-11-08 2022-09-30 13F T-MOBILE US CS 872590104 307,511 117,072 61.47 41,259 61.03 2.9086
2022-07-20 2022-06-30 13F T-MOBILE US CS 872590104 190,439 190,439 25,622 1.7640
2021-11-04 2021-09-30 13F T-MOBILE US CS 872590104 0 -6,849 -100.00 0 -100.00
2021-08-03 2021-06-30 13F T-MOBILE US CS 872590104 6,849 693 11.26 992 28.66 0.0616
2021-05-11 2021-03-31 13F T-MOBILE US CS 872590104 6,156 154 2.57 771 -4.70 0.0505
2021-02-10 2020-12-31 13F T-MOBILE US CS 872590104 6,002 146 2.49 809 20.75 0.0550
2020-11-04 2020-09-30 13F T-MOBILE US CS 872590104 5,856 5,856 670 0.0503
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.