- LeisureMedia 360
- Lion's Roar Foundation
- Lippincott Williams & Wilkins
- Long Thread Media LLC
- Lumina Media
- M Shanken Communications Inc.
- Madavor Media Llc
- Maher Publications
- Maker Media Inc.
- Mansueto Ventures LLC
- Maplegate Media Publishing
- Maritime Publishing
- Martha Stewart Living
- Maven
- McLean Communications
- Media DC
- Media Source Inc
- Media360LLC
- Mental Floss Llc
- Metrocorp, Inc
- Metropolis
- Midwest Outdoors
- Miller Sports Group
- Milwaukee Magazine Inc/Mcgeary
- Minute Media
- MissouriLife
- MIT
- Moffly Publications, Inc.
- Morris Media Network
- Mother Jones
- Motor Trend Group
- Motorsports Marketing
- MovieMaker Magazine
- Murphos Publishing
- Music Maker Publications, Inc.
- National Audubon Society
- National Geographic Society
- National Review Inc
- National Wildlife Federation
- Natural History Magazine Inc
- Nevada Magazine
- New England Home
- New Hope Communications Llc
- New Jersey Monthly
- New Mexico Magazine
- Northwoods Sporting Journal
- NTVB Media Inc.
- O'Meara Brown Publications, Inc.
- Old Mill Road Media
- On Tap Publishing LLC
- Opera News
- Organic Spa Magazine, Ltd.
- Our Media
- Outdoor Sportsman Group
- Outside Interactive, Inc.
- Pacific Standard
- PADI
- Paisano Publications, LLC.
- Paragraph Publishing Ltd
- Penny Press
- Penske Media
- Penske Media Corporation
- Penthouse Global Media
- Poets & Writers, Inc.
- Professional Rodeo Cowboys Association
- Project M Group LLC
- Publications International, LTD
- Purcell Enterprises
- PWX Solutions
- Quadra Media LLC
- Racer Media & Marketing
- Reason Foundation
- Recurrent Ventures Inc
- Red Bull
- Red Engine, LLC
- Redan, Inc.
- Redstone Media Group, Inc.
- Reiman Publications