Mayville Engineering Company, Inc.
US ˙ NYSE ˙ US5786051079

SecurityMEC / Mayville Engineering Company, Inc.
InstitutionVanguard Group Inc
Latest Disclosed Ownership627,655 shares
Latest Disclosed Value $ 11,749,701
Vanguard Group Inc reports 27.99% decrease in ownership of MEC / Mayville Engineering Company, Inc.

On January 29, 2026 - Vanguard Group Inc filed a 13F-HR form disclosing ownership of 627,655 shares of Mayville Engineering Company, Inc. (US:MEC) valued at $11,749,702 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 7, 2025 disclosing 871,659 shares of Mayville Engineering Company, Inc.. This represents a change in shares of -27.99% during the quarter. The current value of the position is $20,511,765 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)
2026-01-29 2025-12-31 13F MAYVILLE ENGR COM 578605107 627,655 -244,004 -27.99 11,750 -2.04 0.0002
2025-11-07 2025-09-30 13F MAYVILLE ENGR COM 578605107 871,659 -10,536 -1.19 11,994 -14.81 0.0002
2025-08-11 2025-06-30 13F MAYVILLE ENGR COM 578605107 882,195 266,049 43.18 14,080 70.16 0.0002
2025-05-09 2025-03-31 13F MAYVILLE ENGR COM 578605107 616,146 -17,606 -2.78 8,275 -16.94 0.0001
2025-02-11 2024-12-31 13F MAYVILLE ENGR COM 578605107 633,752 62,223 10.89 9,963 -17.31 0.0002
2024-11-13 2024-09-30 13F MAYVILLE ENGR COM 578605107 571,529 12,148 2.17 12,048 29.27 0.0002
2024-08-13 2024-06-30 13F MAYVILLE ENGR COM 578605107 559,381 21,206 3.94 9,319 20.84 0.0002
2024-05-10 2024-03-31 13F MAYVILLE ENGR COM 578605107 538,175 39,460 7.91 7,712 7.25 0.0002
2024-03-11 2023-12-31 13F/A-1 MAYVILLE ENGR COM 578605107 498,715 7,564 1.54 7,191 33.49 0.0002
2024-02-14 2023-12-31 13F MAYVILLE ENGR COM 578605107 498,715 7,564 7,191 0.0001
2023-12-18 2023-09-30 13F/A-1 MAYVILLE ENGR COM 578605107 491,151 23,975 5.13 5,388 -7.46 0.0001
2023-11-14 2023-09-30 13F MAYVILLE ENGR COM 578605107 491,151 23,975 5,388 0.0000
2023-08-14 2023-06-30 13F MAYVILLE ENGR COM 578605107 467,176 55,643 13.52 5,821 -5.20 0.0001
2023-07-14 2023-03-31 13F/A-1 MAYVILLE ENGR COM 578605107 411,533 23,816 6.14 6,140 25.10 0.0002
2023-05-15 2023-03-31 13F MAYVILLE ENGR COM 578605107 411,533 23,816 6,140 0.0000
2023-02-10 2022-12-31 13F MAYVILLE ENGR COM 578605107 387,717 8,233 2.17 4,908 98.70 0.0001
2022-11-14 2022-09-30 13F MAYVILLE ENGR COM 578605107 379,484 19,448 5.40 2,470 -11.37 0.0001
2022-08-12 2022-06-30 13F MAYVILLE ENGR COM 578605107 360,036 -37,797 -9.50 2,787 -25.24 0.0001
2022-05-13 2022-03-31 13F MAYVILLE ENGR COM 578605107 397,833 28,009 7.57 3,728 -32.39 0.0001
2022-02-14 2021-12-31 13F MAYVILLE ENGR COM 578605107 369,824 -43,390 -10.50 5,514 -29.03 0.0001
2021-11-12 2021-09-30 13F MAYVILLE ENGR COM 578605107 413,214 -167,652 -28.86 7,769 -33.49 0.0002
2021-08-13 2021-06-30 13F MAYVILLE ENGR COM 578605107 580,866 -20,367 -3.39 11,681 35.12 0.0003
2021-05-14 2021-03-31 13F MAYVILLE ENGINEERING COM 578605107 601,233 9,836 1.66 8,645 8.92 0.0002
2021-02-12 2020-12-31 13F MAYVILLE ENGINEERING COM 578605107 591,397 3,388 0.58 7,937 46.87 0.0002
2020-11-16 2020-09-30 13F MAYVILLE ENGINEERING COM 578605107 588,009 205,901 53.89 5,404 79.00 0.0002
2020-08-14 2020-06-30 13F MAYVILLE ENGINEERING COM 578605107 382,108 -11,267 -2.86 3,019 25.17 0.0001
2020-05-15 2020-03-31 13F MAYVILLE ENGINEERING COM 578605107 393,375 80,331 25.66 2,412 -17.85 0.0001
2020-02-14 2019-12-31 13F MAYVILLE ENGINEERING COM 578605107 313,044 81,185 35.01 2,936 -3.99 0.0001
2019-11-14 2019-09-30 13F MAYVILLE ENGINEERING COM 578605107 231,859 45,628 24.50 3,058 18.99 0.0001
2019-08-14 2019-06-30 13F MAYVILLE ENGINEERING COM 578605107 186,231 186,231 2,570 0.0001
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.