American Tower Corporation
US ˙ NYSE ˙ US03027X1000

SecurityAMT / American Tower Corporation
InstitutionAlly Financial Inc.
Latest Disclosed Ownership31,000 shares
Latest Disclosed Value $ 5,349,980
Ally Financial Inc. ownership in AMT / American Tower Corporation

On May 12, 2026 - Ally Financial Inc. filed a 13F-HR form disclosing ownership of 31,000 shares of American Tower Corporation (US:AMT) valued at $5,349,980 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 31,000 shares of American Tower Corporation. This represents a change in shares of 0.00% during the quarter. The current value of the position is $6,011,210 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)
2026-05-12 2026-03-31 13F American Tower COM 03027X100 31,000 0 0.00 5,350 -1.71 0.6656
2026-02-13 2025-12-31 13F American Tower COM 03027X100 31,000 7,000 29.17 5,443 17.92 0.6646
2025-11-13 2025-09-30 13F American Tower COM 03027X100 24,000 16,000 200.00 4,616 161.03 0.5699
2025-08-13 2025-06-30 13F American Tower COM 03027X100 8,000 -19,000 -70.37 1,768 -69.91 0.1997
2025-05-14 2025-03-31 13F American Tower COM 03027X100 27,000 9,000 50.00 5,875 77.98 0.6592
2025-02-13 2024-12-31 13F American Tower COM 03027X100 18,000 18,000 3,301 0.4026
2024-11-13 2024-09-30 13F American Tower COM 03027X100 0 -32,000 -100.00 0 -100.00
2024-08-13 2024-06-30 13F American Tower COM 03027X100 32,000 9,000 39.13 6,220 36.88 0.7715
2024-05-14 2024-03-31 13F American Tower COM 03027X100 23,000 3,000 15.00 4,545 5.26 0.6135
2024-02-13 2023-12-31 13F American Tower COM 03027X100 20,000 0 0.00 4,318 31.26 0.5642
2023-11-13 2023-09-30 13F American Tower COM 03027X100 20,000 0 0.00 3,289 -15.19 0.4835
2023-08-11 2023-06-30 13F American Tower COM 03027X100 20,000 20,000 3,879 0.5426
2021-11-10 2021-09-30 13F American Tower COM 03027X100 0 -10,000 -100.00 0 -100.00
2021-08-13 2021-06-30 13F American Tower COM 03027X100 10,000 0 0.00 2,701 12.97 0.2682
2021-05-14 2021-03-31 13F American Tower COM 03027X100 10,000 0 0.00 2,391 6.50 0.2280
2021-02-12 2020-12-31 13F American Tower COM 03027X100 10,000 10,000 2,245 0.2108
2016-02-12 2015-12-31 13F American Tower REI 03027X100 0 -25,000 -100.00 0 -100.00
2015-11-13 2015-09-30 13F American Tower REI 03027X100 25,000 0 0.00 2,199 -5.70 0.2232
2015-08-14 2015-06-30 13F American Tower REIT 03027X100 25,000 10,000 66.67 2,332 65.16 0.2361
2015-05-15 2015-03-31 13F American Tower REIT 03027X100 15,000 15,000 1,412 0.1461
2014-08-14 2014-06-30 13F American Tower COM 03027X100 0 -100,000 -100.00 0 -100.00
2014-05-15 2014-03-31 13F American Tower COM 03027X100 100,000 0 0.00 8,187 2.57 0.8724
2014-02-14 2013-12-31 13F American Tower COM 03027X100 100,000 0 0.00 7,982 7.68 0.8493
2013-11-14 2013-09-30 13F American Tower COM 03027X100 100,000 15,000 17.65 7,413 19.20 0.8079
2013-08-14 2013-06-30 13F American Tower COM 03027X100 85,000 85,000 6,219 0.6116
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.