Who owns MTSI (MTSI)
Which tracked institutional funds hold MTSI, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See MTSI 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
216 tracked funds added or opened MTSI while 84 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
MTSI’s largest tracked holder by dollar value, FMR LLC, sizes it at 0.1% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 0.1pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in MTSI 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 512 tracked filers holding MTSI, 278 increased or opened the position and 224 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 MTSI 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 49
- VANGUARD PORTFOLIO MANAGEMENT LLC$797M
- VANGUARD CAPITAL MANAGEMENT LLC$665M
- Polar Capital Holdings Plc$207M
- VANGUARD FIDUCIARY TRUST CO$90M
- E20 Capital Ltd$30M
- CloudAlpha Capital Management Limited/Hong Kong$17M
Full exits 25
- VANGUARD GROUP INC$1.2B
- Capitolis Liquid Global Markets LLC$47M
- D. E. Shaw & Co., Inc.$16M
- IEQ CAPITAL, LLC$10M
- TUDOR INVESTMENT CORP ET AL$9M
- PUBLIC SECTOR PENSION INVESTMENT BOARD$5M
Largest adds
- FMR LLC$1.2B
- T. Rowe Price Investment Management, Inc.$510M
- BlackRock, Inc.$402M
- JPMORGAN CHASE & CO$233M
- Invesco Ltd.$207M
- WELLINGTON MANAGEMENT GROUP LLP$169M
Largest trims
- PRICE T ROWE ASSOCIATES INC /MD/$128M
- Point72 Asset Management, L.P.$67M
- FengHe Fund Management Pte. Ltd.$66M
- ALLIANCEBERNSTEIN L.P.$47M
- DIMENSIONAL FUND ADVISORS LP$45M
- MILLENNIUM MANAGEMENT LLC$29M
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 |
|---|---|---|---|---|
| FMR LLC added | 10,590,263 | $2.4B | 14.1% | 2026-Q1 |
| BlackRock, Inc. added | 7,612,246 | $1.7B | 10.1% | 2026-Q1 |
| T. Rowe Price Investment Management, Inc. added | 4,486,082 | $996M | 6.0% | 2026-Q1 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 3,587,081 | $797M | 4.8% | 2026-Q1 |
| Invesco Ltd. added | 3,575,617 | $794M | 4.7% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 2,992,851 | $665M | 4.0% | 2026-Q1 |
| STATE STREET CORP added | 2,152,751 | $478M | 2.9% | 2026-Q1 |
| JPMORGAN CHASE & CO added | 2,015,630 | $422M | 2.5% | 2026-Q1 |
| WELLINGTON MANAGEMENT GROUP LLP added | 1,543,501 | $343M | 2.1% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 1,359,534 | $302M | 1.8% | 2026-Q1 |
| Capital Research Global Investors trimmed | 1,222,672 | $272M | 1.6% | 2026-Q1 |
| Whale Rock Capital Management LLC added | 1,174,991 | $261M | 1.6% | 2026-Q1 |
| Artisan Partners Limited Partnership trimmed | 1,047,159 | $233M | 1.4% | 2026-Q1 |
| Polar Capital Holdings Plc added | 930,778 | $207M | 1.2% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ trimmed | 914,850 | $203M | 1.2% | 2026-Q1 |
| GW&K Investment Management, LLC trimmed | 839,062 | $186M | 1.1% | 2026-Q1 |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ added | 828,448 | $184M | 1.1% | 2026-Q1 |
| UBS Group AG trimmed | 809,410 | $180M | 1.1% | 2026-Q1 |
| NEUBERGER BERMAN GROUP LLC added | 788,819 | $175M | 1.0% | 2026-Q1 |
| JANUS HENDERSON GROUP PLC added | 784,118 | $174M | 1.0% | 2026-Q1 |
| BARCLAYS PLC added | 734,568 | $163M | 1.0% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 660,860 | $147M | 0.9% | 2026-Q1 |
| NOMURA ASSET MANAGEMENT INTERNATIONAL INC. trimmed | 635,061 | $141M | 0.8% | 2026-Q1 |
| ALLIANCEBERNSTEIN L.P. trimmed | 789,042 | $135M | 0.8% | 2026-Q1 |
| CITADEL ADVISORS LLC added | 590,570 | $131M | 0.8% | 2026-Q1 |
| RAYMOND JAMES FINANCIAL INC trimmed | 590,338 | $127M | 0.8% | 2026-Q1 |
| MORGAN STANLEY trimmed | 555,156 | $123M | 0.7% | 2026-Q1 |
| BESSEMER GROUP INC trimmed | 533,257 | $118M | 0.7% | 2026-Q1 |
| NORTHERN TRUST CORP added | 532,682 | $118M | 0.7% | 2026-Q1 |
| DIMENSIONAL FUND ADVISORS LP trimmed | 529,138 | $117M | 0.7% | 2026-Q1 |
| Stephens Investment Management Group LLC trimmed | 515,820 | $115M | 0.7% | 2026-Q1 |
| FRANKLIN RESOURCES INC added | 501,969 | $111M | 0.7% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ trimmed | 480,687 | $107M | 0.6% | 2026-Q1 |
| Rafferty Asset Management, LLC trimmed | 467,587 | $104M | 0.6% | 2026-Q1 |
| Analog Century Management LP trimmed | 436,346 | $97M | 0.6% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC trimmed | 430,800 | $96M | 0.6% | 2026-Q1 |
| CITIGROUP INC added | 423,865 | $94M | 0.6% | 2026-Q1 |
| VANGUARD FIDUCIARY TRUST CO new | 405,532 | $90M | 0.5% | 2026-Q1 |
| Bank of New York Mellon Corp added | 400,926 | $89M | 0.5% | 2026-Q1 |
| NORGES BANK added | 770,377 | $77M | 0.5% | 2026-Q1 |
| GENEVA CAPITAL MANAGEMENT LLC trimmed | 343,759 | $76M | 0.5% | 2026-Q1 |
| AMERICAN CENTURY COMPANIES INC trimmed | 343,287 | $76M | 0.5% | 2026-Q1 |
| TimesSquare Capital Management, LLC added | 341,231 | $76M | 0.5% | 2026-Q1 |
| Driehaus Capital Management LLC trimmed | 336,813 | $75M | 0.4% | 2026-Q1 |
| MILLENNIUM MANAGEMENT LLC trimmed | 335,214 | $74M | 0.4% | 2026-Q1 |
| LOOMIS SAYLES & CO L P trimmed | 322,459 | $72M | 0.4% | 2026-Q1 |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE trimmed | 305,954 | $68M | 0.4% | 2026-Q1 |
| JENNISON ASSOCIATES LLC trimmed | 299,725 | $67M | 0.4% | 2026-Q1 |
| LORD, ABBETT & CO. LLC added | 253,398 | $56M | 0.3% | 2026-Q1 |
| NEW YORK STATE COMMON RETIREMENT FUND trimmed | 242,938 | $54M | 0.3% | 2026-Q1 |
| SCHRODER INVESTMENT MANAGEMENT GROUP trimmed | 250,048 | $52M | 0.3% | 2026-Q1 |
| FIRST TRUST ADVISORS LP added | 228,400 | $51M | 0.3% | 2026-Q1 |
| Fiera Capital Corp trimmed | 224,740 | $50M | 0.3% | 2026-Q1 |
| TD Asset Management Inc trimmed | 221,374 | $49M | 0.3% | 2026-Q1 |
| SEI INVESTMENTS CO added | 219,363 | $49M | 0.3% | 2026-Q1 |
| OBERWEIS ASSET MANAGEMENT INC/ added | 215,886 | $48M | 0.3% | 2026-Q1 |
| Nuveen, LLC added | 212,296 | $47M | 0.3% | 2026-Q1 |
| AQR CAPITAL MANAGEMENT LLC trimmed | 211,385 | $46M | 0.3% | 2026-Q1 |
| Aristotle Capital Boston, LLC trimmed | 206,116 | $46M | 0.3% | 2026-Q1 |
| SEGALL BRYANT & HAMILL, LLC trimmed | 200,859 | $45M | 0.3% | 2026-Q1 |
| PRINCIPAL FINANCIAL GROUP INC added | 195,148 | $43M | 0.3% | 2026-Q1 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC added | 190,789 | $42M | 0.3% | 2026-Q1 |
| Amundi added | 187,067 | $42M | 0.2% | 2026-Q1 |
| Squarepoint Ops LLC added | 172,153 | $38M | 0.2% | 2026-Q1 |
| RHUMBLINE ADVISERS added | 166,173 | $37M | 0.2% | 2026-Q1 |
| AMERIPRISE FINANCIAL INC trimmed | 155,118 | $34M | 0.2% | 2026-Q1 |
| Ranger Investment Management, L.P. trimmed | 148,356 | $33M | 0.2% | 2026-Q1 |
| BNP PARIBAS FINANCIAL MARKETS trimmed | 146,406 | $33M | 0.2% | 2026-Q1 |
| E20 Capital Ltd new | 136,829 | $30M | 0.2% | 2026-Q1 |
| Swiss National Bank added | 133,550 | $30M | 0.2% | 2026-Q1 |
| WESTFIELD CAPITAL MANAGEMENT CO LP trimmed | 132,457 | $29M | 0.2% | 2026-Q1 |
| NEXT CENTURY GROWTH INVESTORS LLC added | 130,256 | $29M | 0.2% | 2026-Q1 |
| PUBLIC EMPLOYEES RETIREMENT ASSOCIATION OF COLORADO trimmed | 127,629 | $28M | 0.2% | 2026-Q1 |
| Point72 Asset Management, L.P. trimmed | 125,722 | $28M | 0.2% | 2026-Q1 |
| Silverberg Bernstein Capital Management LLC trimmed | 123,250 | $27M | 0.2% | 2026-Q1 |
| SILVERCREST ASSET MANAGEMENT GROUP LLC trimmed | 118,169 | $26M | 0.2% | 2026-Q1 |
| DEUTSCHE BANK AG\ added | 117,561 | $26M | 0.2% | 2026-Q1 |
| ENVESTNET ASSET MANAGEMENT INC trimmed | 115,592 | $26M | 0.2% | 2026-Q1 |
| FengHe Fund Management Pte. Ltd. trimmed | 110,526 | $25M | 0.1% | 2026-Q1 |
| California Public Employees Retirement System added | 110,216 | $24M | 0.1% | 2026-Q1 |
| Retirement Systems of Alabama added | 108,486 | $24M | 0.1% | 2026-Q1 |
| Mirae Asset Global Investments Co., Ltd. added | 106,529 | $24M | 0.1% | 2026-Q1 |
| KENNEDY CAPITAL MANAGEMENT LLC trimmed | 105,241 | $23M | 0.1% | 2026-Q1 |
| VICTORY CAPITAL MANAGEMENT INC trimmed | 97,524 | $22M | 0.1% | 2026-Q1 |
| BALYASNY ASSET MANAGEMENT L.P. trimmed | 95,261 | $21M | 0.1% | 2026-Q1 |
| Legal & General Group Plc trimmed | 89,647 | $20M | 0.1% | 2026-Q1 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP added | 85,035 | $19M | 0.1% | 2026-Q1 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM added | 79,391 | $18M | 0.1% | 2026-Q1 |
| ROYAL BANK OF CANADA trimmed | 78,001 | $17M | 0.1% | 2026-Q1 |
| CloudAlpha Capital Management Limited/Hong Kong added | 77,214 | $17M | 0.1% | 2026-Q1 |
| LMR Partners LLP added | 75,000 | $17M | 0.1% | 2026-Q1 |
| THORNBURG INVESTMENT MANAGEMENT INC trimmed | 74,613 | $17M | 0.1% | 2026-Q1 |
| Gotham Asset Management, LLC added | 71,605 | $16M | 0.1% | 2026-Q1 |
| Universal- Beteiligungs- und Servicegesellschaft mbH trimmed | 71,293 | $16M | 0.1% | 2026-Q1 |
| VANGUARD GROUP INC added | 7,133,670 | $1.2B | 7.3% | 2025-Q4 stale |
| MACQUARIE GROUP LTD added | 859,784 | $107M | 0.6% | 2025-Q3 stale |
| Capitolis Liquid Global Markets LLC added | 274,000 | $47M | 0.3% | 2025-Q4 stale |
| EMERALD ADVISERS, LLC trimmed | 143,085 | $18M | 0.1% | 2025-Q3 stale |
| RENAISSANCE TECHNOLOGIES LLC added | 131,215 | $16M | 0.1% | 2025-Q3 stale |
| D. E. Shaw & Co., Inc. trimmed | 93,298 | $16M | 0.1% | 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.