Tet Corporation

In The Dark Tower series of novels by Stephen King, the Tet Corporation was founded by Roland Deschain and his ka-tet to prevent the destruction of The Rose by stopping the Sombra Corporation from purchasing the vacant lot on which the rose grew.

In the novel series, a near infinite number of parallel universes are all held together or ruled from the Dark Tower, an edifice of infinite power. Each reality that was preserved by the Dark Tower contained a manifestation of the Tower itself. In one particular reality (the reality of Earth, the reality which we inhabit), the incarnation of the Tower is represented by a single red wild rose growing in a vacant lot in Manhattan. In the novel, an evil corporation owned by the Crimson King seeks to destroy and/or dominate our universe by taking possession of the lot and bulldozing over the rose.

To preserve their quest for the actual Tower and save our universe in the process, the hero of the novels, Roland Deschain, used the financial resources of a member of his group (ka-tet), Susannah Dean-specifically, the dental fortune her father, an inventor, entrusted to her uncle-to purchase the lot under the name of the Tet Corporation. This phantom company bought the lot to protect it from the malefic Sombra Corporation, headed by the Crimson King (Roland's Archenemy) and thus save our dimension of the universe from ultimate destruction. The Tet Corporation built a black skyscraper on the lot without harming or even moving the rose. The skyscraper, located at 2 Hammarskjöld Plaza, was believed by Roland to be the Dark Tower's image in that world, built to protect the rose.

In the seventh and final book of the series, Roland is introduced to the modern-day head of the Tet corporation: Moses Carver's daughter, born after Susannah departed New York for Roland's world. Moses Carver is the last living 'founding father', ceding control to his daughter after the deaths of John Cullum and Aaron Deepneau. The Tet Corporation is revealed to use a mixture of modern technology as well as supernatural, monitoring Roland's progress with a team of trained psychics and even training their own Gunslingers (one of whom is Carver's own daughter). They also review books written by Stephen King, in hopes of finding information that relates to the Dark Tower. In a meeting with Roland, they restore to him the silver cross given to him by Aunt Talitha in The Wastelands (to whom he promised it would be carried with him to the Tower), valuable information regarding his path towards the Dark Tower, and the Stephen King book Insomnia.

2 Hammarskjöld Plaza is an actual building upon which an actual Black skyscraper stands, likely the reason Stephen King chose this building to be the location of the rose.