| MGMarquette Gas | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MPMartinez Produce & Seafood, Inc. | Chicago | IL | Food Manufacturing311710 | — | ◇ UNVERIFIED |
| MOMartin Oil of Indiana 709 | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MAMarvel Abrasive Products, LLC | Chicago | IL | Nonmetallic Mineral Product Manufacturing327910 | — | ◇ UNVERIFIED |
| MMMarv-O-Lus Manufacturing Company | Chicago | IL | Fabricated Metal Product Manufacturing332618 | — | ◇ UNVERIFIED |
| MCMaster Casting and CAD | Chicago | IL | Miscellaneous Manufacturing339910 | — | ◇ UNVERIFIED |
| MGMaster Gauge CO. | Chicago | IL | Computer and Electronic Product Manufacturing334513 | — | ◇ UNVERIFIED |
| MWMatthew Warren, INC. Dba Automatic Spring Coiling, CO. | Chicago | IL | Fabricated Metal Product Manufacturing332612 | — | ◇ UNVERIFIED |
| MIMauritzon INC | Chicago | IL | Textile Product Mills314912 | — | ◇ UNVERIFIED |
| MWMccormick West Constructors LLC | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MMMcdonnell & Miller Itt | Chicago | IL | Machinery Manufacturing333414 | — | ◇ UNVERIFIED |
| MPMel-lo Popcorn Specialties CO | Chicago | IL | Food Manufacturing311999 | — | ◇ UNVERIFIED |
| MSMellow Sweet, Inc. dba Jaafer Sweets | Chicago | IL | Food Manufacturing311811 | — | ◇ UNVERIFIED |
| MLMelpap LTD Dba Cm Morton | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MPMenasha Packaging CO LLC | Chicago | IL | Machinery Manufacturing333244 | — | ◇ UNVERIFIED |
| MPMercury Plastics, INC Dba Felpak | Chicago | IL | Plastics and Rubber Products Manufacturing326199 | — | ◇ UNVERIFIED |
| MPMetal Partners Rebar, LLC | Chicago | IL | Primary Metal Manufacturing331210 | — | ◇ UNVERIFIED |
| MAMetro Auto Tech United | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MBMetropolitan Brewing, LLC | Chicago | IL | Beverage and Tobacco Product Manufacturing312120 | — | ◇ UNVERIFIED |
| MSMeyer Steel Drum, INC. | Chicago | IL | Fabricated Metal Product Manufacturing332439 | — | ◇ UNVERIFIED |
| MGM & G Graphics, INC. | Chicago | IL | Printing and Related Support Activities323111 | — | ◇ UNVERIFIED |
| MEMico Express | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MTMicro Thread Corporation | Chicago | IL | Fabricated Metal Product Manufacturing332721 | — | ◇ UNVERIFIED |
| MPMidamerican Printing Systems INC | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MIMidland Industries INC | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MGMidway Gas Service INC | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MGMidwest Generation LLC | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MMMidwest Manufacturing and Distributing, INC. Dba Midwest Metal Forming | Chicago | IL | Fabricated Metal Product Manufacturing332322 | — | ◇ UNVERIFIED |
| MMMidwest Mycelium LLC | Chicago | IL | Food Manufacturing311920 | — | ◇ UNVERIFIED |
| MIMifab INC | Chicago | IL | Fabricated Metal Product Manufacturing332812 | — | ◇ UNVERIFIED |
| MMMiles Mcneel Design inc. | Chicago | IL | Miscellaneous Manufacturing339910 | — | ◇ UNVERIFIED |
| MPMiller Products INC | Chicago | IL | Printing and Related Support Activities323111 | — | ◇ UNVERIFIED |
| MPMiracle Press CO | Chicago | IL | Printing and Related Support Activities323111 | — | ◇ UNVERIFIED |
| MVMjd Ventures LLC | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MEMks Energies INC | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MMobil | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MMobil | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MSModern Sprout LLC | Chicago | IL | Furniture and Related Product Manufacturing337110 | — | ◇ UNVERIFIED |
| MSModern Sprout LLC | Chicago | IL | Chemical Manufacturing325611 | — | ◇ UNVERIFIED |
| MCMollys Cupcakes Chicago LLC | Chicago | IL | Food Manufacturing311811 | — | ◇ UNVERIFIED |
| MMMonami Mobil 2 | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MWMonda Window & Door, CORP. | Chicago | IL | Fabricated Metal Product Manufacturing332321 | — | ◇ UNVERIFIED |
| MLMonosol LLC | Chicago | IL | Plastics and Rubber Products Manufacturing326113 | — | ◇ UNVERIFIED |
| MPMps Paper Tube & Can | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| MOMrc Operations, LLC | Chicago | IL | Chemical Manufacturing325211 | — | ◇ UNVERIFIED |
| MIMw Ii INC | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| NDNakamon Design LLC | Chicago | IL | Miscellaneous Manufacturing339910 | — | ◇ UNVERIFIED |
| NMNational Material Processing, LLC | Chicago | IL | Primary Metal Manufacturing331110 | — | ◇ UNVERIFIED |
| NPNational Processing Company | Chicago | IL | Primary Metal Manufacturing331210 | — | ◇ UNVERIFIED |
| NINavistar, INC | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
