Politics and Business magazines
- MCI Communications Corporation
- MCI WorldCom, Inc.
- McIlhenny Company
- McJunkin Corporation
- McKechnie plc
- McKinsey & Company, Inc.
- McLane Company, Inc.
- McLeodUSA Incorporated
- McMenamins Pubs and Breweries
- MCN Corporation
- McPherson's Ltd.
- MCSi, Inc.
- MDC Partners Inc
- Mead Data Central, Inc.
- Mead Johnson & Company
- Meade Instruments Corporation
- Meadowcraft, Inc.
- MeadWestvaco Corporation
- Measurement Specialties, Inc.
- Mecalux S.A.