Who owns ADTRAN Holdings (ADTN)
Which tracked institutional funds hold ADTN, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See ADTN company fundamentals →
Ownership as of the 2026-Q1 13F filings (latest filed 2026-05-18). 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
The tracked-fund tape on ADTN is one-sided between 2025-Q4 and 2026-Q1: 110 added or opened and 26 trimmed or exited — on balance accumulating.
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
ADTN’s largest tracked holder by dollar value, BlackRock, Inc., sizes it at 0.0% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 0.0pp gap the other way — the median holder sizes ADTN more heavily than its largest holder by dollar value does.
Book-share is each fund’s reported value in ADTN 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 226 tracked filers holding ADTN, 135 increased or opened the position and 100 reduced or closed it; over the same quarter, open-market insider Form 4 buying and selling roughly offset.
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 ADTN 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 22
- VANGUARD PORTFOLIO MANAGEMENT LLC$60M
- VANGUARD CAPITAL MANAGEMENT LLC$43M
- Shannon River Fund Management LLC$15M
- Boston Partners$15M
- MARSHALL WACE, LLP$11M
- HEARTLAND ADVISORS INC$9M
Full exits 12
- VANGUARD GROUP INC$71M
- Ophir Asset Management Pty Ltd$9M
- Alyeska Investment Group, L.P.$5M
- Atom Investors LP$4M
- Niles Investment Management, LLC$1M
- HUSSMAN STRATEGIC ADVISORS, INC.$1M
Largest adds
- BlackRock, Inc.$28M
- ROYCE & ASSOCIATES LP$17M
- JPMORGAN CHASE & CO$15M
- TWO SIGMA INVESTMENTS, LP$14M
- STATE STREET CORP$12M
- DNB Asset Management AS$12M
Largest trims
- Assenagon Asset Management S.A.$4M
- Hillsdale Investment Management Inc.$4M
- Divisar Capital Management LLC$4M
- JANE STREET GROUP, LLC$2M
- ALLIANCEBERNSTEIN L.P.$1M
- BNP PARIBAS FINANCIAL MARKETS$879K
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 | 7,836,196 | $109M | 9.3% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 4,771,452 | $60M | 5.1% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 3,426,230 | $43M | 3.7% | 2026-Q1 |
| STATE STREET CORP added | 3,082,794 | $43M | 3.7% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP added | 2,896,353 | $40M | 3.4% | 2026-Q2 |
| ROYCE & ASSOCIATES LP added | 3,127,403 | $39M | 3.4% | 2026-Q1 |
| DNB Asset Management AS | 3,123,679 | $39M | 3.4% | 2026-Q1 |
| MILLENNIUM MANAGEMENT LLC added | 2,722,820 | $38M | 3.2% | 2026-Q2 |
| WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC trimmed | 1,989,530 | $25M | 2.1% | 2026-Q1 |
| RENAISSANCE TECHNOLOGIES LLC added | 1,773,740 | $25M | 2.1% | 2026-Q2 |
| MORGAN STANLEY added | 1,832,872 | $23M | 2.0% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 1,819,123 | $23M | 2.0% | 2026-Q1 |
| Divisar Capital Management LLC trimmed | 1,769,439 | $22M | 1.9% | 2026-Q1 |
| JPMORGAN CHASE & CO added | 1,518,697 | $19M | 1.6% | 2026-Q1 |
| First Eagle Investment Management, LLC trimmed | 1,248,507 | $17M | 1.5% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP added | 1,337,028 | $17M | 1.4% | 2026-Q1 |
| SG Americas Securities, LLC added | 1,316,049 | $17M | 1.4% | 2026-Q1 |
| NEEDHAM INVESTMENT MANAGEMENT LLC trimmed | 1,228,500 | $15M | 1.3% | 2026-Q1 |
| Shannon River Fund Management LLC new | 1,219,976 | $15M | 1.3% | 2026-Q1 |
| D. E. Shaw & Co., Inc. trimmed | 1,091,898 | $15M | 1.3% | 2026-Q2 |
| Boston Partners new | 1,181,314 | $15M | 1.3% | 2026-Q1 |
| MARSHALL WACE, LLP added | 1,038,292 | $14M | 1.2% | 2026-Q2 |
| FMR LLC added | 1,011,195 | $14M | 1.2% | 2026-Q2 |
| SEI INVESTMENTS CO added | 1,105,110 | $14M | 1.2% | 2026-Q1 |
| Tieton Capital Management, LLC added | 1,035,167 | $13M | 1.1% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC added | 970,707 | $12M | 1.0% | 2026-Q1 |
| BARCLAYS PLC trimmed | 927,775 | $12M | 1.0% | 2026-Q1 |
| FEDERATED HERMES, INC. added | 922,616 | $12M | 1.0% | 2026-Q1 |
| Squarepoint Ops LLC added | 887,962 | $11M | 1.0% | 2026-Q1 |
| Point72 Asset Management, L.P. added | 764,780 | $11M | 0.9% | 2026-Q2 |
| WESTERLY CAPITAL MANAGEMENT, LLC added | 800,000 | $10M | 0.9% | 2026-Q1 |
| HEARTLAND ADVISORS INC new | 750,000 | $9M | 0.8% | 2026-Q1 |
| Kovack Advisors, Inc. trimmed | 736,000 | $9M | 0.8% | 2026-Q1 |
| AQR CAPITAL MANAGEMENT LLC trimmed | 671,403 | $9M | 0.8% | 2026-Q2 |
| PARADIGM CAPITAL MANAGEMENT INC/NY trimmed | 733,200 | $9M | 0.8% | 2026-Q1 |
| Trexquant Investment LP added | 684,909 | $9M | 0.7% | 2026-Q1 |
| NORTHERN TRUST CORP added | 659,248 | $8M | 0.7% | 2026-Q1 |
| NORGES BANK added | 575,400 | $8M | 0.7% | 2026-Q2 |
| 1492 Capital Management LLC added | 625,024 | $8M | 0.7% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC trimmed | 624,112 | $8M | 0.7% | 2026-Q1 |
| TUDOR INVESTMENT CORP ET AL trimmed | 541,455 | $8M | 0.6% | 2026-Q2 |
| HRT FINANCIAL LP added | 568,126 | $7M | 0.6% | 2026-Q1 |
| Connor, Clark & Lunn Investment Management Ltd. added | 560,348 | $7M | 0.6% | 2026-Q1 |
| Kerrisdale Advisers, LLC new | 552,010 | $7M | 0.6% | 2026-Q1 |
| VANGUARD FIDUCIARY TRUST CO new | 522,530 | $7M | 0.6% | 2026-Q1 |
| NOMURA HOLDINGS INC trimmed | 464,176 | $6M | 0.5% | 2026-Q1 |
| JACOBS LEVY EQUITY MANAGEMENT, INC added | 461,681 | $6M | 0.5% | 2026-Q1 |
| Assenagon Asset Management S.A. trimmed | 457,952 | $6M | 0.5% | 2026-Q1 |
| ROYAL BANK OF CANADA trimmed | 457,402 | $6M | 0.5% | 2026-Q1 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP added | 455,647 | $6M | 0.5% | 2026-Q1 |
| CITADEL ADVISORS LLC added | 381,544 | $5M | 0.4% | 2026-Q1 |
| WELLS FARGO & COMPANY/MN trimmed | 378,572 | $5M | 0.4% | 2026-Q1 |
| MACKENZIE FINANCIAL CORP added | 368,680 | $5M | 0.4% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ added | 367,226 | $5M | 0.4% | 2026-Q1 |
| Lisanti Capital Growth, LLC added | 336,965 | $4M | 0.4% | 2026-Q1 |
| Nuveen, LLC added | 335,189 | $4M | 0.4% | 2026-Q1 |
| BALYASNY ASSET MANAGEMENT L.P. added | 275,489 | $4M | 0.3% | 2026-Q2 |
| WHITE PINE CAPITAL LLC trimmed | 294,369 | $4M | 0.3% | 2026-Q1 |
| CRAMER ROSENTHAL MCGLYNN LLC new | 287,178 | $4M | 0.3% | 2026-Q1 |
| Qube Research & Technologies Ltd added | 269,945 | $3M | 0.3% | 2026-Q1 |
| Invesco Ltd. trimmed | 236,765 | $3M | 0.3% | 2026-Q2 |
| DEUTSCHE BANK AG\ trimmed | 258,657 | $3M | 0.3% | 2026-Q1 |
| Manatuck Hill Partners, LLC added | 250,000 | $3M | 0.3% | 2026-Q1 |
| STATE OF WISCONSIN INVESTMENT BOARD trimmed | 249,706 | $3M | 0.3% | 2026-Q1 |
| UBS Group AG added | 249,157 | $3M | 0.3% | 2026-Q1 |
| Bank of New York Mellon Corp trimmed | 240,001 | $3M | 0.3% | 2026-Q1 |
| Skandinaviska Enskilda Banken AB (publ) added | 235,188 | $3M | 0.3% | 2026-Q1 |
| ALGERT GLOBAL LLC trimmed | 228,160 | $3M | 0.2% | 2026-Q1 |
| Engineers Gate Manager LP added | 218,511 | $3M | 0.2% | 2026-Q1 |
| AMERICAN CENTURY COMPANIES INC trimmed | 216,262 | $3M | 0.2% | 2026-Q1 |
| HERALD INVESTMENT MANAGEMENT Ltd | 200,000 | $3M | 0.2% | 2026-Q1 |
| RAYMOND JAMES FINANCIAL INC trimmed | 191,995 | $2M | 0.2% | 2026-Q1 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC added | 190,238 | $2M | 0.2% | 2026-Q1 |
| Inspire Investing, LLC added | 182,522 | $2M | 0.2% | 2026-Q1 |
| AMERIPRISE FINANCIAL INC trimmed | 171,956 | $2M | 0.2% | 2026-Q1 |
| BNP PARIBAS FINANCIAL MARKETS trimmed | 170,769 | $2M | 0.2% | 2026-Q1 |
| Walleye Trading LLC added | 154,896 | $2M | 0.2% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 138,630 | $2M | 0.2% | 2026-Q2 |
| ACADIAN ASSET MANAGEMENT LLC added | 147,706 | $2M | 0.2% | 2026-Q1 |
| Swiss National Bank added | 142,600 | $2M | 0.2% | 2026-Q1 |
| OCCUDO QUANTITATIVE STRATEGIES LP added | 100,956 | $2M | 0.2% | 2026-Q1 |
| Brevan Howard Capital Management LP trimmed | 124,994 | $2M | 0.1% | 2026-Q2 |
| OP Asset Management Ltd new | 115,374 | $2M | 0.1% | 2026-Q1 |
| GLOBEFLEX CAPITAL L P added | 132,417 | $2M | 0.1% | 2026-Q1 |
| Lido Advisors, LLC added | 129,330 | $2M | 0.1% | 2026-Q1 |
| LANDSCAPE CAPITAL MANAGEMENT, L.L.C. added | 128,002 | $2M | 0.1% | 2026-Q1 |
| VICTORY CAPITAL MANAGEMENT INC trimmed | 123,600 | $2M | 0.1% | 2026-Q1 |
| Legato Capital Management LLC added | 123,100 | $2M | 0.1% | 2026-Q1 |
| VANGUARD GROUP INC trimmed | 8,188,496 | $71M | 6.1% | 2025-Q4 stale |
| Focus Partners Wealth new | 109,183 | $27M | 2.3% | 2025-Q3 stale |
| Ophir Asset Management Pty Ltd trimmed | 1,069,420 | $9M | 0.8% | 2025-Q4 stale |
| SG Capital Management LLC new | 847,417 | $8M | 0.6% | 2025-Q2 stale |
| Cubist Systematic Strategies, LLC added | 585,145 | $5M | 0.5% | 2025-Q3 stale |
| Alyeska Investment Group, L.P. trimmed | 545,464 | $5M | 0.4% | 2025-Q4 stale |
| Atom Investors LP added | 439,946 | $4M | 0.3% | 2025-Q4 stale |
| Apis Capital Advisors, LLC new | 435,000 | $4M | 0.3% | 2025-Q1 stale |
| WOLVERINE ASSET MANAGEMENT LLC new | 260,400 | $2M | 0.2% | 2025-Q3 stale |
| Walleye Capital LLC added | 238,963 | $2M | 0.2% | 2025-Q2 stale |
| SummitTX Capital, L.P. new | 204,474 | $2M | 0.2% | 2025-Q1 stale |
| MOORE CAPITAL MANAGEMENT, LP new | 174,330 | $2M | 0.1% | 2025-Q3 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.