Dex One Corporation was an American marketing company providing online, mobile and print search marketing via their DexKnows.com website, print yellow pages directories and pay-per-click ad networks in the U.S. In April 2013 Dex One merged with SuperMedia, and the combined company (after further acquisitions) now does business as Thryv Inc. History Dex One Corporation was originally established as the R.H. Donnelley Company in 1886 by Reuben H. Donnelley, son of RR Donnelley founder Richard R. Donnelley. R.H. Donnelley primarily contracted with The Chicago Telephone Company to publish telephone directories for Chicago telephone customers. In 1906, the company began contracting with Bell System firms such as New York Telephone, Wisconsin Telephone, and Cincinnati Suburban Telephone Co. In 1917, The R.H. Donnelley Company was incorporated and moved to New York City, retaining some offices in Chicago. In 1929, Reuben Donnelley died; his company remained and continued to contract with the Bell System to publish telephone directories nationally. In 1961, R. H. Donnelley became a wholly owned subsidiary of Dun & Bradstreet. Partnerships Following its merger with Dun & Bradstreet, the company began a series of partnerships with additional telephone companies to publish directories. Around this time, competition started with other phone companies to provide directories. From 1980 to 1985, R.H. Donnelley began a partnership with United Telephone (Sprint), called Uni-Don, to publish telephone directories to customers in central Florida. In 1986, it contracted with NYNEX to become its directory sales agent. The same year, R.H. Donnelley started publishing directories in Delaware, New Jersey, and Pennsylvania in competition with Bell Atlantic, although a lot of these areas were later sold off to Yellow Book. In 1988, it formed Cen-Don with Centel (now part of CenturyLink) to publish telephone directories in Florida, Illinois, Iowa, Minnesota, Nevada, North Carolina, Ohio, and Virginia. Venture One was formed with Southwestern Bell Corporation, which published directories in competition with Bell Atlantic in Baltimore, MD and Washington, D.C. In 1990, DonTech was formed with Ameritech to publish telephone directories in Illinois and northwest Indiana. Public offering On July 1, 1998, Dun & Bradstreet split into two companies, one assuming the Dun & Bradstreet name, while the other adopting the R.H. Donnelley name. In 2002, R.H. Donnelley acquired Sprint Directory Publishing, the publishing unit of Sprint Corp. In 2003, R.H. Donnelley Publishing & Advertising, Inc., which published directories under the EMBARQ Yellow Pages name, was acquired from the Sprint