Who owns AMT (AMT)
Which tracked institutional funds hold AMT, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See AMT company fundamentals →
Ownership as of the 2026-Q1 13F filings. 13F is disclosed up to 45 days after quarter-end, so the most recent quarter fills in over the following weeks.
How the tape is positioned
337 tracked funds added or opened AMT while 400 trimmed or exited it between 2025-Q4 and 2026-Q1 — the tape is split. When large holders disagree on a name, the funds moving first are sometimes ahead of the story.
A prompt to read the filings, not a verdict. 13F is a quarter-end snapshot disclosed up to 45 days late; a fund adds or exits for mandate, benchmark, and timing reasons that have nothing to do with a view on the stock. This is a starting question, not a signal to trade.
Conviction spread
AMT’s largest tracked holder by dollar value, VANGUARD GROUP INC, sizes it at 0.2% of its own reported 13F book, while the median holder sizes it at 0.2% of theirs — a 0.0pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in AMT divided by its whole reported 13F book, so it is comparable across funds of different sizes and is unaffected by stock splits. A higher share means a fund has committed more of its book to the name — a starting question about conviction, not a verdict or a signal to trade.
Institutional & insider positioning
Between 2025-Q4 and 2026-Q1, across 1740 tracked filers holding AMT, 872 increased or opened the position and 839 reduced or closed it; over the same quarter, open-market insider Form 4s were net purchases.
This fuses two public signals for the same quarter — how tracked institutions changed their positions and whether insiders bought or sold in the open market. It describes what was filed; it is a starting question, not a verdict or a signal to trade.
New buyers & exits
Funds opening or closing a position in AMT between the 2025-Q4 and 2026-Q1 13F filings, and the largest changes among funds holding it in both. New buyers and exits are counted on fund presence (split-invariant); adds and trims are measured on reported value.
New buyers 60
- VANGUARD CAPITAL MANAGEMENT LLC$5.2B
- VANGUARD PORTFOLIO MANAGEMENT LLC$4.8B
- VANGUARD FIDUCIARY TRUST CO$466M
- CIBC Bancorp USA Inc.$234M
- Vanguard Global Advisers, LLC$177M
- VANGUARD ASSET MANAGEMENT, Ltd$140M
Full exits 68
- VANGUARD GROUP INC$11.2B
- CIBC Private Wealth Group LLC$205M
- TWO SIGMA ADVISERS, LP$76M
- ALKEON CAPITAL MANAGEMENT LLC$75M
- CCLA Investment Management$73M
- CIBC WORLD MARKETS CORP$66M
Largest adds
- FEDERATED HERMES, INC.$372M
- Capital World Investors$237M
- LAZARD ASSET MANAGEMENT LLC$196M
- Point72 Asset Management, L.P.$194M
- NORGES BANK$153M
- GOLDMAN SACHS GROUP INC$133M
Largest trims
- BlackRock, Inc.$490M
- Capital International Investors$482M
- FRANKLIN RESOURCES INC$360M
- NORTHWESTERN MUTUAL WEALTH MANAGEMENT CO$308M
- PRICE T ROWE ASSOCIATES INC /MD/$171M
- AQR CAPITAL MANAGEMENT LLC$158M
Institutional holders
One row per tracked fund, largest reported value first. “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding. Rows marked stale are from an earlier filing than the security’s latest quarter — that fund is absent from the newest snapshot (position exited, or reported under a different name).
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| BlackRock, Inc. trimmed | 41,956,261 | $7.2B | 9.4% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 30,362,380 | $5.2B | 6.8% | 2026-Q1 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 27,596,159 | $4.8B | 6.2% | 2026-Q1 |
| STATE STREET CORP added | 21,434,609 | $3.7B | 4.8% | 2026-Q1 |
| JPMORGAN CHASE & CO added | 15,128,367 | $2.6B | 3.4% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 13,933,628 | $2.4B | 3.1% | 2026-Q1 |
| COHEN & STEERS, INC. added | 12,619,866 | $2.2B | 2.8% | 2026-Q1 |
| FMR LLC trimmed | 11,316,728 | $2.0B | 2.5% | 2026-Q1 |
| MORGAN STANLEY trimmed | 9,583,923 | $1.7B | 2.2% | 2026-Q1 |
| DEUTSCHE BANK AG\ added | 7,769,353 | $1.3B | 1.7% | 2026-Q1 |
| NORGES BANK trimmed | 6,085,223 | $1.3B | 1.7% | 2026-Q1 |
| LAZARD ASSET MANAGEMENT LLC added | 7,325,943 | $1.3B | 1.6% | 2026-Q1 |
| Invesco Ltd. added | 7,175,690 | $1.2B | 1.6% | 2026-Q1 |
| PRINCIPAL FINANCIAL GROUP INC trimmed | 5,914,591 | $1.0B | 1.3% | 2026-Q1 |
| DIMENSIONAL FUND ADVISORS LP trimmed | 5,811,041 | $1.0B | 1.3% | 2026-Q1 |
| Capital World Investors added | 5,667,888 | $978M | 1.3% | 2026-Q1 |
| NORTHERN TRUST CORP trimmed | 5,339,734 | $922M | 1.2% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 5,240,288 | $904M | 1.2% | 2026-Q1 |
| Legal & General Group Plc trimmed | 4,825,921 | $833M | 1.1% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ trimmed | 4,774,353 | $824M | 1.1% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC added | 4,697,393 | $811M | 1.1% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ added | 4,511,662 | $779M | 1.0% | 2026-Q1 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC added | 4,339,494 | $749M | 1.0% | 2026-Q1 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP trimmed | 4,195,978 | $724M | 0.9% | 2026-Q1 |
| Capital Research Global Investors added | 4,103,353 | $708M | 0.9% | 2026-Q1 |
| Nuveen, LLC trimmed | 3,889,182 | $671M | 0.9% | 2026-Q1 |
| Amundi added | 3,830,533 | $661M | 0.9% | 2026-Q1 |
| Clearbridge Investments, LLC added | 3,685,476 | $636M | 0.8% | 2026-Q1 |
| WELLS FARGO & COMPANY/MN added | 3,501,851 | $604M | 0.8% | 2026-Q1 |
| UBS Group AG trimmed | 3,488,057 | $602M | 0.8% | 2026-Q1 |
| FRANKLIN RESOURCES INC trimmed | 3,343,526 | $577M | 0.8% | 2026-Q1 |
| AMERIPRISE FINANCIAL INC trimmed | 3,310,593 | $571M | 0.7% | 2026-Q1 |
| Bank of New York Mellon Corp added | 2,773,447 | $479M | 0.6% | 2026-Q1 |
| FEDERATED HERMES, INC. added | 2,756,058 | $476M | 0.6% | 2026-Q1 |
| VANGUARD FIDUCIARY TRUST CO new | 2,699,678 | $466M | 0.6% | 2026-Q1 |
| CANADA PENSION PLAN INVESTMENT BOARD added | 2,386,605 | $412M | 0.5% | 2026-Q1 |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE trimmed | 2,315,919 | $400M | 0.5% | 2026-Q1 |
| NORDEA INVESTMENT MANAGEMENT AB added | 2,044,852 | $350M | 0.5% | 2026-Q1 |
| Fisher Asset Management, LLC trimmed | 1,736,413 | $300M | 0.4% | 2026-Q1 |
| ROYAL BANK OF CANADA added | 1,645,003 | $284M | 0.4% | 2026-Q1 |
| Cantillon Capital Management LLC trimmed | 1,612,473 | $278M | 0.4% | 2026-Q1 |
| BARROW HANLEY MEWHINNEY & STRAUSS LLC added | 1,585,600 | $274M | 0.4% | 2026-Q1 |
| HSBC HOLDINGS PLC trimmed | 1,572,977 | $271M | 0.4% | 2026-Q1 |
| RAYMOND JAMES FINANCIAL INC added | 1,551,441 | $268M | 0.3% | 2026-Q1 |
| National Pension Service trimmed | 1,533,703 | $265M | 0.3% | 2026-Q1 |
| Magellan Asset Management Ltd added | 1,503,296 | $259M | 0.3% | 2026-Q1 |
| SG Americas Securities, LLC added | 1,382,740 | $239M | 0.3% | 2026-Q1 |
| Swiss National Bank added | 1,373,900 | $237M | 0.3% | 2026-Q1 |
| CIBC Bancorp USA Inc. added | 1,358,233 | $234M | 0.3% | 2026-Q1 |
| AMERICAN CENTURY COMPANIES INC trimmed | 1,349,347 | $233M | 0.3% | 2026-Q1 |
| LORING WOLCOTT & COOLIDGE FIDUCIARY ADVISORS LLP/MA trimmed | 1,216,494 | $218M | 0.3% | 2026-Q1 |
| BARCLAYS PLC trimmed | 1,255,920 | $217M | 0.3% | 2026-Q1 |
| TWO SIGMA INVESTMENTS, LP added | 1,226,889 | $212M | 0.3% | 2026-Q1 |
| Sumitomo Mitsui Trust Group, Inc. added | 1,220,578 | $211M | 0.3% | 2026-Q1 |
| BNP PARIBAS FINANCIAL MARKETS added | 1,212,291 | $209M | 0.3% | 2026-Q1 |
| Point72 Asset Management, L.P. added | 1,205,312 | $208M | 0.3% | 2026-Q1 |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. added | 1,166,809 | $201M | 0.3% | 2026-Q1 |
| Capital International Investors trimmed | 1,143,814 | $197M | 0.3% | 2026-Q1 |
| D. E. Shaw & Co., Inc. trimmed | 1,131,650 | $195M | 0.3% | 2026-Q1 |
| M&G PLC added | 1,115,542 | $193M | 0.3% | 2026-Q1 |
| Heard Capital LLC trimmed | 1,112,105 | $192M | 0.3% | 2026-Q1 |
| CBRE INVESTMENT MANAGEMENT LISTED REAL ASSETS LLC added | 1,110,227 | $192M | 0.2% | 2026-Q1 |
| NEUBERGER BERMAN GROUP LLC trimmed | 1,068,844 | $184M | 0.2% | 2026-Q1 |
| Mitsubishi UFJ Asset Management Co., Ltd. added | 1,065,693 | $184M | 0.2% | 2026-Q1 |
| CANADA LIFE ASSURANCE Co added | 1,030,753 | $179M | 0.2% | 2026-Q1 |
| ENVESTNET ASSET MANAGEMENT INC added | 1,033,938 | $178M | 0.2% | 2026-Q1 |
| Vanguard Global Advisers, LLC new | 1,024,070 | $177M | 0.2% | 2026-Q1 |
| DAVENPORT & Co LLC trimmed | 1,026,871 | $176M | 0.2% | 2026-Q1 |
| MILLENNIUM MANAGEMENT LLC added | 1,021,378 | $176M | 0.2% | 2026-Q1 |
| RHUMBLINE ADVISERS trimmed | 995,150 | $172M | 0.2% | 2026-Q1 |
| Swedbank AB added | 953,557 | $165M | 0.2% | 2026-Q1 |
| California Public Employees Retirement System trimmed | 938,126 | $162M | 0.2% | 2026-Q1 |
| Russell Investments Group, Ltd. added | 937,962 | $162M | 0.2% | 2026-Q1 |
| DUFF & PHELPS INVESTMENT MANAGEMENT CO added | 920,890 | $159M | 0.2% | 2026-Q1 |
| COMMONWEALTH OF PENNSYLVANIA PUBLIC SCHOOL EMPLS RETRMT SYS trimmed | 918,264 | $158M | 0.2% | 2026-Q1 |
| CITADEL ADVISORS LLC trimmed | 876,763 | $151M | 0.2% | 2026-Q1 |
| SEI INVESTMENTS CO added | 867,418 | $150M | 0.2% | 2026-Q1 |
| Sarasin & Partners LLP trimmed | 863,166 | $149M | 0.2% | 2026-Q1 |
| Aberdeen Group plc added | 852,623 | $147M | 0.2% | 2026-Q1 |
| LPL Financial LLC added | 849,192 | $147M | 0.2% | 2026-Q1 |
| Man Group plc trimmed | 826,138 | $143M | 0.2% | 2026-Q1 |
| US BANCORP \DE\ trimmed | 816,817 | $141M | 0.2% | 2026-Q1 |
| VANGUARD ASSET MANAGEMENT, Ltd new | 812,950 | $140M | 0.2% | 2026-Q1 |
| STOREBRAND ASSET MANAGEMENT AS trimmed | 797,602 | $138M | 0.2% | 2026-Q1 |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC added | 791,418 | $137M | 0.2% | 2026-Q1 |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. trimmed | 783,649 | $135M | 0.2% | 2026-Q1 |
| Allianz Asset Management GmbH trimmed | 760,688 | $131M | 0.2% | 2026-Q1 |
| MARSHALL WACE, LLP added | 751,254 | $130M | 0.2% | 2026-Q1 |
| WELLINGTON MANAGEMENT GROUP LLP added | 739,087 | $128M | 0.2% | 2026-Q1 |
| ACADIAN ASSET MANAGEMENT LLC added | 735,606 | $127M | 0.2% | 2026-Q1 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM trimmed | 682,040 | $118M | 0.2% | 2026-Q1 |
| ALLIANCEBERNSTEIN L.P. added | 656,026 | $115M | 0.2% | 2026-Q1 |
| LASALLE INVESTMENT MANAGEMENT SECURITIES LLC added | 648,257 | $112M | 0.1% | 2026-Q1 |
| CITIGROUP INC added | 633,831 | $109M | 0.1% | 2026-Q1 |
| MILFORD FUNDS LTD trimmed | 621,018 | $107M | 0.1% | 2026-Q1 |
| AQR CAPITAL MANAGEMENT LLC trimmed | 572,540 | $98M | 0.1% | 2026-Q1 |
| Corient Private Wealth LLC trimmed | 546,827 | $94M | 0.1% | 2026-Q1 |
| VANGUARD GROUP INC added | 63,754,871 | $11.2B | 14.6% | 2025-Q4 stale |
| VIKING GLOBAL INVESTORS LP added | 2,797,125 | $618M | 0.8% | 2025-Q2 stale |
| CIBC Private Wealth Group LLC trimmed | 1,166,450 | $205M | 0.3% | 2025-Q4 stale |
Ownership over time
Tracked institutional holder count and total shares held by filing quarter (independent scales). The curated-era tail and any mid-ingest latest quarter are handled honestly — a partial quarter is not drawn as a collapse.
Reading this table
Funds hold the same stock for different reasons — an index fund “holds” almost everything, an active manager sizes a name to a mandate and a benchmark, and each fund entered at its own price and time. Because 13F is filed up to 45 days after quarter-end, every row is a backward-looking snapshot; a manager may have traded since. Share-class siblings (a company’s A and C shares) are rolled up to one line so a dual-class name is never double-counted. Compare like-for-like. A large holder is not an endorsement, and a fund exiting is not a warning — this is a starting question, not a verdict.
About 13F filings
A Form 13F is a quarterly disclosure that institutional investment managers with over $100 million in US-listed equities must file with the SEC. In plain English: it is a snapshot of the long stock positions a fund held at the end of a quarter. It covers long US-listed equities only — not short positions, options, cash, or private holdings — and the funds shown are the large sample we track, not the complete 13F universe.