MEC Mayville Engineering Company, Inc.
Mayville Engineering Company, Inc. (MEC) Institutional Ownership
What the institutions did with MEC last quarter, from their 13F filings. Counting managers rather than shares is the point: a single index fund adding to a position tells you far less than four hundred separate managers all deciding to. Positions as reported for the quarter ended June 30, 2026.
Every manager below opens. Subscribers can see any firm's whole portfolio — every position, its weight, and what they bought, trimmed and exited last quarter.
Sign in or subscribeLargest holders
| Manager | Shares | % of reported |
|---|---|---|
| Portolan Capital Management, LLC | 1.3M | 6.1% |
| FMR LLC | 1.3M | 6.0% |
| BlackRock, Inc. | 1.2M | 5.6% |
| Allspring Global Investments Holdings, LLC | 1.1M | 5.1% |
| Driehaus Capital Management LLC | 846.4K | 4.0% |
| SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC | 800.0K | 3.8% |
| DIMENSIONAL FUND ADVISORS LP | 782.3K | 3.7% |
| ROYCE & ASSOCIATES LP | 752.1K | 3.6% |
| VANGUARD CAPITAL MANAGEMENT LLC | 743.6K | 3.5% |
| Boston Partners | 696.4K | 3.3% |
| Jupiter Topco LLC | 575.3K | 2.7% |
| BLAIR WILLIAM & CO/IL | 546.7K | 2.6% |
| WELLINGTON MANAGEMENT GROUP LLP | 477.6K | 2.3% |
| EVR Research LP | 441.9K | 2.1% |
| GEODE CAPITAL MANAGEMENT, LLC | 374.6K | 1.8% |
| First Eagle Investment Management, LLC | 369.6K | 1.7% |
| JANE STREET GROUP, LLC | 356.2K | 1.7% |
| JPMORGAN CHASE & CO | 347.2K | 1.6% |
| KENNEDY CAPITAL MANAGEMENT LLC | 336.4K | 1.6% |
| Ophir Asset Management Pty Ltd | 326.7K | 1.5% |
| Granahan Investment Management, LLC | 324.1K | 1.5% |
| SILVERCREST ASSET MANAGEMENT GROUP LLC | 313.9K | 1.5% |
| STATE STREET CORP | 291.2K | 1.4% |
| Nuveen, LLC | 281.9K | 1.3% |
| BANK OF AMERICA CORP /DE/ | 276.3K | 1.3% |
Largest changes
| Manager | Action | Previous | Current | Change |
|---|---|---|---|---|
| FMR LLC | Increased | 4.3K | 1.3M | +1.3M |
| Allspring Global Investments Holdings, LLC | Reduced | 2.0M | 1.1M | -927.4K |
| Driehaus Capital Management LLC | New | 0 | 846.4K | +846.4K |
| SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC | New | 0 | 800.0K | +800.0K |
| Portolan Capital Management, LLC | Increased | 821.1K | 1.3M | +478.1K |
| WELLINGTON MANAGEMENT GROUP LLP | New | 0 | 477.6K | +477.6K |
| Boston Partners | Increased | 232.6K | 696.4K | +463.8K |
| JANE STREET GROUP, LLC | New | 0 | 356.2K | +356.2K |
| AMERIPRISE FINANCIAL INC | Sold Out | 351.8K | 0 | -351.8K |
| JPMORGAN CHASE & CO | Increased | 5.5K | 347.2K | +341.7K |
| Ophir Asset Management Pty Ltd | New | 0 | 326.7K | +326.7K |
| BlackRock, Inc. | Increased | 881.9K | 1.2M | +301.6K |
| Nuveen, LLC | Increased | 47.4K | 281.9K | +234.5K |
| KENNEDY CAPITAL MANAGEMENT LLC | Increased | 106.8K | 336.4K | +229.6K |
| Roubaix Capital, LLC | Sold Out | 210.7K | 0 | -210.7K |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP | Sold Out | 185.3K | 0 | -185.3K |
| AWM Investment Company, Inc. | New | 0 | 180.0K | +180.0K |
| EVR Research LP | Reduced | 620.0K | 441.9K | -178.1K |
| OSTERWEIS CAPITAL MANAGEMENT INC | New | 0 | 174.6K | +174.6K |
| AMERICAN CENTURY COMPANIES INC | Reduced | 221.7K | 48.2K | -173.5K |
| TUDOR INVESTMENT CORP ET AL | New | 0 | 169.8K | +169.8K |
| TWO SIGMA INVESTMENTS, LP | Increased | 34.7K | 198.9K | +164.2K |
| LORD, ABBETT & CO. LLC | New | 0 | 152.2K | +152.2K |
| VANGUARD CAPITAL MANAGEMENT LLC | Increased | 594.9K | 743.6K | +148.7K |
| DIMENSIONAL FUND ADVISORS LP | Reduced | 926.2K | 782.3K | -143.9K |
13F filings are due 45 days after quarter end and cover long positions in U.S.-listed equities only, so this is a lagged and partial picture: shorts, bonds and foreign listings never appear. Options positions are excluded here rather than folded into the share counts. Political ownership is coming.