- MANE — Veradermics, Incorporated
- MANH — Manhattan Associates, Inc.
- MANI — Man Active Income ETF
- MANT — ManTech International Corporation
- MANU — Manchester United plc
- MAPIX — Matthews Asia Dividend Fund Investor Class
- MAPOX — Mairs & Power Balanced Fund Investor Class
- MAPP — Harbor Multi-Asset Explorer ETF (MAPP)
- MAPPX — MSIF Advantage Portfolio Class A
- MAPS.V — ProStar Holdings Inc.
- MAPTX — Matthews Pacific Tiger Fund Investor Class
- MAQCW — Maquia Capital Acquisition Corporation
- MAR — Marriott International, Inc.
- MARA — Marathon Digital Holdings, Inc.
- MARB — First Trust Merger Arbitrage ETF
- MARI.TO — Marimaca Copper Corp.
- MARNX — Convergence Long/Short Equity Fund Institutional Class
- MARO — YieldMax MARA Option Income Strategy ETF
- MARPS — Marine Petroleum Trust
- MARX — Mars Acquisition Corp.
- MARXU — Mars Acquisition Corp.
- MAS — Masco Corporation
- MAS.V — MAS Gold Corp.
- MASFX — iMGP Alternative Strategies Fund
- MASGX — Matthews Emerging Markets Sustainable Future Fund
- MASI — Masimo Corporation
- MASK — 3 E Network Technology Group Ltd Class A Ordinary Shares
- MASKX — iShares Russell 2000 Small-Cap Index Fund
- MASNX — iMGP Alternative Strategies Fund
- MASS — 908 Devices Inc.
- MASS.V — Masivo Silver Corp.
- MASTX — BMO Large-Cap Growth Fund Class Y
- MAT — Mattel, Inc.
- MATA.V — Matador Technologies Inc.
- MATFX — Matthews Asia Innovators Fund
- MATH — Metalpha Technology Holding Limited
- MATR — Mattersight Corporation
- MATR.TO — Mattr Corp.
- MATV — Mativ Holdings, Inc.
- MATW — Matthews International Corporation
- MATX — Matson, Inc.
- MAU.TO — Montage Gold Corp.
- MAU.V — Montage Gold Corp.
- MAV — Pioneer Municipal High Income Advantage Fund, Inc.
- MAV.TO — MAV Beauty Brands Inc.
- MAVF — Matrix Advisors Value ETF
- MAVFX — EA Series Trust - Matrix Advisors Value ETF
- MAW.TO — Mawson Gold Limited
- MAX — MediaAlpha, Inc.
- MAX.V — Max Resource Corp.
- MAXI — Simplify Bitcoin Strategy PLUS Income ETF
- MAXN — Maxeon Solar Technologies, Ltd.
- MAXR — Maxar Technologies Inc.
- MAXR.TO — Maxar Technologies Inc.
- MAYA — Maywood Acquisition Corp.
- MAYAR — Maywood Acquisition Corp. Right
- MAYAU — Maywood Acquisition Corp. Unit
- MAYHX — BlackRock High Yield Municipal Fund
- MAYS — J.W. Mays, Inc.
- MAZE — Maze Therapeutics, Inc.
- MB — MASTERBEEF GROUP
- MBA.TO — CIBT Education Group Inc.
- MBAC — M3-Brigade Acquisition II Corp.
- MBAC-UN — M3-Brigade Acquisition II Corp.
- MBAI — Check-Cap Ltd. Ordinary Share
- MBAV — M3-Brigade Acquisition V Corp. Class A Ordinary shares
- MBAVU — M3-Brigade Acquisition V Corp. Units
- MBAVW — M3-Brigade Acquisition V Corp.
- MBB — iShares MBS ETF
- MBBC — Marathon Bancorp, Inc.
- MBC — MasterBrand, Inc.
- MBCN — Middlefield Banc Corp.
- MBEAX — AMG GW&K Global Allocation Fund Class N
- MBESX — AMG GW&K Global Allocation Fund
- MBEYX — AMG GW&K Global Allocation Fund
- MBFIP — MB Financial Capital Trust I, 8.60% Cumulative Trust Preferred Securities
- MBG — SPDR Bloomberg Barclays Mortgage Backed Bond ETF
- MBGL — Mobility Global Inc
- MBGVX — AMG GW&K Core Bond ESG Fund - Class N
- MBI — MBIA Inc.
- MBII — Marrone Bio Innovations, Inc.
- MBIN — Merchants Bancorp
- MBINL — Merchants Bancorp
- MBINM — Merchants Bancorp
- MBINN — Merchants Bancorp
- MBINO — Merchants Bancorp
- MBINP — Merchants Bancorp
- MBIO — Mustang Bio, Inc.
- MBLY — Mobileye Global Inc.
- MBN.TO — MBN Corporation
- MBNKP — Medallion Bank
- MBO.V — Mobio Technologies Inc.
- MBOT — Microbot Medical Inc.
- MBOX — Freedom Day Dividend ETF
- MBRG — Middleburg Financial Corp.
- MBRX — Moleculin Biotech, Inc.
- MBS — Angel Oak Mortgage-Backed Securities ETF
- MBSC — M3-Brigade Acquisition III Corp.
- MBSC-UN — M3-Brigade Acquisition III Corp.
- MBSD — FlexShares Disciplined Duration MBS Index Fund
