Alien technology refers to engineered objects, materials, or capabilities of non-human origin, usually assumed to be extraterrestrial. In UAP debate the phrase covers two different claim families. One holds that governments or defense contractors have recovered non-human craft and studied them for decades. The other is a scientific search for artifacts or signals made elsewhere in the universe. Neither has produced an artifact or record that has been publicly confirmed as non-human.

The recovery narrative grew from the 1947 Roswell story and was popularized by Bob Lazar, who said in 1989 that he had worked on alien propulsion systems at a site called S-4 near Area 51, a claim that remains disputed. Its modern form rests on former intelligence officer David Grusch, who testified to Congress in 2023 that the United States runs a long-running crash-retrieval and reverse-engineering program, based largely on accounts from other officials. Senators Chuck Schumer and Mike Rounds wrote "technologies of unknown origin" into their 2023 disclosure bill. In 2026, former Rep. Matt Gaetz said he believed the U.S. military had benefited from acquiring and reverse-engineering technology not indigenous to its own defense ecosystem, and filmmaker James Fox said the executive branch had approved congressional visits to sites allegedly holding it.

The official record does not support those claims. The Pentagon's All-domain Anomaly Resolution Office reported in 2024 that it found no verifiable evidence that the U.S. government or private industry had ever had access to, or reverse-engineered, extraterrestrial technology, and it traced many recovery stories to misidentified real programs and circular reporting. The best-known physical sample, layered magnesium-alloy fragments known as "Art's Parts" and claimed to come from Roswell, was judged terrestrial in an Oak Ridge National Laboratory analysis for AARO, while the Colombian "Buga sphere" promoted in 2025 has never been independently analyzed. Supporters of the recovery narrative argue that the relevant programs sit outside AARO's reach.

The scientific strand runs separately. Harvard astrophysicist Avi Loeb argues that interstellar objects passing through the solar system should be examined as possible technology. In October 2026, as chair of an advisory council to the government's new UAP Governance Board, he urged the Trump administration to examine its best data, including any recovered craft or material if Grusch's claims prove correct, and to gather new sensor data. That proposal captures why alien technology has become the central question of the disclosure debate: unlike sightings, a recovered object or program record is something that could be produced and examined.