1967 - Xerox
1985 - Reed International
2001 - Cambridge Information Group
2006 - CIG purchases ProQuest Information and Learning, renamed to ProQuest LLC the following year, and operates Bowker under the ProQuest division
2021 - Clarivate purchases ProQuest
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On Dec. 27, 1967, stockholders of the R. R. Bowker Company agreed to the sale of the company to the Xerox Corporation. The company had previously been private with internal ownership and continued operating independently after the sale under the Xerox Educational Division. In 1985, Bowker was purchased by Reed International and made a division of Reed Publishing USA, along with Cahners Magazines and Cahners Exposition Group. Bowker was sold to its current owner, Cambridge Information Group in 2001, eventually being repositioned as an affiliate of ProQuest, one of Cambridge's properties. When Clarivate completed its purchase of ProQuest in late 2021, Bowker remained a Cambridge property.
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Xerox to Sell Publishing Units: Gulf+Western to Buy Ginn, Thomson to Buy Bowker, PW, May 3, 1985, at 18.