ProQuest LLC is an Ann Arbor, Michigan-based global information-content and technology company, founded in 1938 as University Microfilms by Eugene Power.

The company began operations as a producer of microfilm products, subsequently shifting to electronic publishing,[3] and later grew through acquisitions.

By June 1938, Power worked in two rented rooms from a downtown Ann Arbor funeral parlor, specializing in microphotography to preserve library collections.

In his autobiography Edition of One, Power details the development of the company, including how University Microfilms assisted the OSS during World War II.

[20] This work mainly involved filming maps and European newspapers so they could be shipped back and forth overseas more cheaply and discreetly.

At a time when modem connections were slow and expensive, it was more efficient to mail database CD-ROMs regularly to subscribing libraries, who installed the discs on dedicated PCs.

In 1998, the company announced the "Digital Vault Initiative", purported to include 5.5 billion images digitized from UMI microfilm, including some of the best existing copies of major newspapers dating back 100 to 150 years, and Early English books dating back to the 15th century.

This acquisition gave Proquest ownership of a 100+ person publishing operation based in Cambridge, England and became the basis for a substantial overseas expansion.

[32] In 2004, ProQuest Information and Learning acquired Seattle start-up Serials Solutions, a venture providing access management and search services for content hosted by other companies.

[33] In 2005 three ProQuest executives formed a distribution company called National Archive Publishing Co, of XanEdu, UMI, and Digital Service Operations.

[34] The building that would house this new company stood at 300 Zeeb Road in Scio, home to nearly 6 billion pages of information.

[39][40] In 2010, ProQuest acquired two properties from LexisNexis, the Congressional Information Service (CIS) and University Publications of America (UPA).

The acquisition included digital products and an expansive microfilm vault that would leverage ProQuest's strength in conversion from film to searchable electronic formats.

[43] In 2014, ProQuest acquired Pi2 Solutions, a privately owned company specializing in Drug Safety Triager (DST) & Product Literature Database (PLD) systems for the biopharmaceutical industry.