Capstone Software was a subsidiary of IntraCorp, a Miami, Florida-based computer and video game company. Capstone created first-person games such as Corridor 7: Alien Invasion, William Shatner's TekWar and Witchaven, and is also well known for releasing games based on movie/TV licenses.
Capstone's logo was a picture of a triangle. Underneath the triangle was their slogan: "The Pinnacle of Entertainment".
IntraCorp went bankrupt in 1996 and shut down all their operations, including Capstone Software. Capstone's last game, Corridor 8: Galactic Wars, never left the prototype stage and was never released. Capstone's first-person games used the Wolfenstein 3D engine, and later, the Build engine (best known for powering 3D Realms' Duke Nukem 3D).
Source: Wikipedia, "Capstone Software," available under the CC-BY-SA License.