International Bible Students Association

A number of corporations are in use by Jehovah's Witnesses. They publish literature and perform other operational and administrative functions, representing the interests of the religious organization. "The Society" has been used as a collective term for these corporations.

The oldest and most prominent of their corporation names, "Watch Tower Society", has also been used synonymously with the religious organization of Jehovah's Witnesses, even in their own literature. Particularly since 2000, Jehovah's Witnesses have maintained a distinction between their corporations and their religious organization.

Watch Tower Bible and Tract Society of Pennsylvania is a non-stock, not-for-profit organization headquartered in the New York City borough of Brooklyn, United States. It is the main legal entity used worldwide by Jehovah's Witnesses, often referred to as "The Society". It holds the copyrights of most literature published by Jehovah's Witnesses. The society was founded in 1881 with William Henry Conley, a Pittsburgh businessman, as the first president and Charles Taze Russell as secretary-treasurer. The society was incorporated as Zion's Watch Tower Tract Society in Pennsylvania on December 15, 1884, with Russell as president. The corporation was officially renamed Watch Tower Bible and Tract Society in 1896; similar names had been in unofficial use since at least 1892.

Watchtower Bible and Tract Society of New York, Inc. is a corporation used by Jehovah's Witnesses, which is responsible for administrative matters, such as real estate, especially within the United States. This corporation is typically cited as the publisher of Jehovah's Witnesses publications, though other publishers are sometimes cited. The corporation's stated purposes are: “Charitable, benevolent, scientific, historical, literary and religious purposes; the moral and mental improvement of men and women, the dissemination of Bible truths in various languages by means of the publication of tracts, pamphlets, papers and other religious documents, and for religious missionary work.”

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