Which company developed the 2007 video game Portal?

Which company developed the 2007 video game Portal? Valve developed Portal.

Portal began with Narbacular Drop, a 2005 student project created at DigiPen Institute of Technology. Valve developer Robin Walker saw the prototype and invited its creators to present it at Valve. The team was subsequently hired, and the portal concept was reworked into a first-person puzzle game set at Aperture Science.

Valve developed Portal with a remarkably small team: no more than 10 people were involved. The game took about two years and four months to complete after the DigiPen team joined Valve. Its design combined spatial puzzles, physics-based movement and dark comedy, with Kim Swift among its designers and Erik Wolpaw and Chet Faliszek among its writers.

A common mix-up is confusing the game's origin with its developer. Narbacular Drop inspired Portal, but it is not the company that developed Portal. Portal was released in 2007 as part of The Orange Box, alongside Half-Life 2 and Team Fortress 2.