Weyland Corporation, also referred to as Weyland Industries or Weyland Corp, was a British corporation that was established by Sir Peter Weyland on October 11, 2012. Its name changed to Weyland-Yutani after the merger with the Japanese company Yutani Corporation.
Often referred to as "The Company" it is one of the many mega-corporations that runs the human colonies outside the solar system through the Extrasolar Colonization Administration, has a seat in the Interstellar Commerce Commission's Company Review Board, and also has a large presence on Earth. They hold their main offices in Tokyo, San Francisco, The Sea of Tranquility, and Thadeus.
Weyland-Yutani consistently exhibits the worst aspects of corporate profiteering, willing to sacrifice decency and human life in seemingly the pursuit of profit. The corporation has consistently ordered its employees and agents to attempt to obtain living Xenomorphs so that they can be exploited as a biological weapon, without regard for their obtainers' lives.

At some point in the 21st Century, the British corporation Weyland Corp eventually merged with the Japanese company Yutani Corporation and became the antecedents to the Weyland-Yutani comglomerate corporation.
In 2122, the commercial hauler Nostromo was on its way to Earth from a job in the Solomons, the Nostromo passed through the Zeta II Reticuli system, the Nostromo's onboard computer, "MU-TH-UR" intercepted a distress beacon originating from a planetoid (which later came to be known as Acheron) within close proximity to the ship. The crew members are awakened prematurely from their hypersleep, the crew responded to the beacon and landed the Nostromo on the planetoid. Executive Officer Kane was impregnated by a parasitic life form discovered within an ancient derelict space craft found on the planet's surface. Kane was taken back to the Nostromo for medical treatment, only to die hours later when the creature that was impregnated within him grew and bursts violently out of his chest while being witnessed by the entire crew. Weyland-Yutani gave orders to Science Officer Ash and "MOTHER" to implement Special Order 937 and ensure the survival of the Xenomorph specimen at any cost and deemed the rest of the Nostromo's crew expendable. The Nostromo was destroyed during the incident and all of its crew were killed by the Xenomorph, except for Ellen Ripley who managed to escape on an emergency vessel and to ultimately kill the Xenomorph.
In December of 2137, Weyland-Yutani purchased Sevastopol Station, a decommissioned trading and manufacturing spaceport in the Zeta Reticuli system, formerly owned by the Seegson Corporation. At the time of the purchase, Sevastopol had a small number of Xenomorphs within the bowels of its structure, and the company, aware of this, bought the for-sale station to acquire the specimens located there. Another reason for the purchase was so the company would be able to modify the core programming of Seegson's APOLLO A.I. control system for Sevastopol, uploading Special Order 939, which allowed the A.I. to cut off communications off-station and preserve any alien specimens. On December 11th, 2137, Sevastopol's orbital stabilizers were damaged by an explosion from the nearby Anesidora, causing the station to fall out of orbit and eventually burn up in the atmosphere of gas giant KG348, killing the Xenomorphs remaining on the station.
57 years later in 2179, Weyland-Yutani representative Carter J. Burke gave orders to Hadley's Hope, a human colony that was established by Weyland-Yutani on Acheron to investigate the ruins of the Derelict spacecraft having learned of its location from Ripley who was rescued after spending the last 57 years adrift in space in hypersleep since her first horrific encounter with the Xenomorph, evidenced from her testimony regarding the Nostromo's destruction. The colonists eventually found the derelict and discovered thousands of Xenomorph eggs in suspended animation. Soon the eggs began to hatch and facehuggers started to impregnate the colonists. The colony was eventually overrun by the Xenomorphs. After the mysterious loss of contact with the colony, Weyland-Yutani sent the USCM to investigate as well as sending Ripley to assist the Marines in the mission and Burke who was given a secret objective to ensure the capture of a Xenomorph specimen. The Colonial Marines eventually came in contact with the Xenomorphs and suffered massive casualties due to the creatures' several advantages, including the element of surprise. The survivors decided to take off and nuke the colony from orbit. They called the drop ship for immediate evacuation; however an alien stowaway on the drop ship killed the pilots causing the drop ship to crash into the processing station causing major damage from which it became unstable and would detonate with the force of a thermonuclear weapon.
While the survivors took refuge in the medical station, Ripley (and Newt, a survivor that was rescued by the Marines earlier) fell asleep in the medical laboratory and were attacked by two Facehuggers that Burke had released from their tanks. Ripley was able to alert the marines who rescued them and killed the creatures. Ripley then accused Burke of trying to impregnate her and Newt to get two alien creatures past Earth's quarantine procedures, and also planning to kill the rest of the marines whilst in hypersleep during the return trip back to Earth. The Xenomorphs then cut the electricity and kill most of the survivors, including Burke. Ripley along with the remaining survivors were able to escape the colony via drop ship and escaped moments before the colony was consumed by the nuclear blast caused by the Atmosphere Processor.
Ripley, along with the three other survivors of Hadley's Hope, crashed on Fiorina 161 when all of their hypersleep chambers were ejected from the Sulaco in an EEV after a Facehugger caused an electrical fire on board. All cryochambers crashed on the correctional facility. Unfortunately, Hicks was impaled by debris in the EEV due to the impact and died. Newt crashed into the ocean and drowned in her hypersleep chamber and Bishop was damaged further whereupon he was placed on a scrap heap by the prisoners on the colony. A Facehugger emerged from the ruins of the EEV and impregnated the prison's dog, Spike. The Xenomorph embryo violently emerged from Spike and began to mature within the correctional facility's ventilation ducts. The Alien began a killing spree in the correctional facility, causing mass hysteria. Ripley rallied the inmates and proposed they pour highly flammable toxic waste, which is stored at the facility, into the ventilation system and ignite it to flush out the creature. An explosion is caused by the Runner's premature intervention, resulting in several deaths.
Weyland-Yutani sent a group of researchers led by Michael Bishop and an elite special forces unit to Fiorina 161 after the company was contacted by Francis Aaron regarding the presence of the Xenomorph. Michael tries to convince Ripley to surrender so that they can extract the Queen embryo within her. Ripley chooses to sacrifice herself in order to keep the company from getting their hands on the Xenomorph and jumps into the molten lead. Aaron was killed after assaulting Michael, Morse was relocated and Weyland-Yutani terminated the prison's contract. The remaining functional lead works apparatus was scrapped and the Fiorina 161 Correctional Unit was closed for an indefinite period.
Despite having to fail in retrieving the Queen embryo from Ripley, Michael decided to board the USS Sulaco to figure out its previous destination in hopes of locating the Xenomorph hive on LV-426. Michael and his research team manage to locate the hive within the ruins of the Hadley's Hope colony and established a research facility to begin to capture Xenomorph specimens for research purposes.
200 years later, USM researcher Mason Wren stated that Weyland-Yutani had been bought out by Wal-Mart decades ago. His comment, ’fortunes of war’ suggests a serious conflict between the United Americas and the Third World Empire, as evidenced by the devastated Paris. Consequently an interstellar military force called "United Systems Military" now controls all the weapons and R&D interests previously held by Weyland-Yutani.