 Miamisburg @-@ based <unk> is the world 's largest data warehousing and enterprise analytics company , and Richfield @-@ based <unk> is the world 's largest online automotive parts exchange , or <unk> . One Call Now , headquartered in Troy , is the nation 's largest information notification service and part of INC Magazine 's fastest @-@ growing companies list three years in a row , while <unk> , headquartered in Mason , is the nation 's leading integrated and automated , personalized communications firm . 
