Lying in a hospital bed in Saudi Arabia, his legs encased in plaster casts, Shrawan Shah Rauniyar clung to the hope that at least he would be fairly compensated. After all, when his legs were crushed under a giant metal beam that fell off a forklift, he was working on a project belonging to one of the most profitable companies in the world: Saudi Aramco.

Rauniyar, a migrant worker from Nepal, was not employed directly by the state-owned energy company, but like tens of thousands of other migrant workers in the Gulf kingdom, he worked for a small labour supply company, which sent him to work on a project managed by the Italian firm Saipem, which in turn was contracted to Aramco.

When staff from Saipem came to visit him in hospital, they brought him some flowers, chocolates and a blunt message. “Don’t ask us about compensation. We don’t know about it. You’re a contract worker for us. Talk to your employer,” Rauniyar alleges.

But the labour supply company appeared in a hurry to wash its hands of him. Men from the company came to threaten Rauniyar in hospital, he says. “Go home. Otherwise, we’ll kill you. We’ll kick you out on the street. Then who will give you food and shelter?” they allegedly told him.

Rauniyar refused to give in and demanded the compensation he was entitled to in his contract and under Saudi law, but less than three weeks after the accident, he claims staff from the labour supply company “forcefully” took him to the airport and put him on a plane back to Nepal.

Saipem confirmed Rauniyar was injured and said it “ensured full medical assistance” for him.

Rauniyar believes some of the responsibility for his fate lies with Aramco. “I get enraged thinking about Aramco. Since it is taking workers from other companies, shouldn’t they pay attention to them? It’s their responsibility, too,” he says. “Aramco has become rich selling our sweat and blood.”

Rauniyar’s story is one of 23 cases of alleged labour rights abuses among workers employed by Aramco’s contractors and subcontractors in Saudi Arabia documented in a report by the human rights group FairSquare. Based on these allegations, the report finds that migrant workers in Aramco’s supply chain “are exposed to serious safety and health risks, and face significant challenges in claiming compensation in the event of injury or death”.

Workers interviewed by FairSquare alleged they also endured grave labour rights violations, which included exposure to extreme heat, work shifts of up to 19 hours and being put up in what the rights group calls “slum housing”.

FairSquare’s director, Nick McGeehan, said: “Aramco obviously has a responsibility to protect these workers, but it also has tremendous influence to set standards that flow down its supply chain to hundreds of thousands of workers across Saudi Arabia. The neglect that we see in its supply chain indicates that it takes migrant worker protection no more seriously than the Saudi state.”

The findings are particularly striking given that Aramco is one of the wealthiest, most profitable and influential corporations in the world. As Saudi Arabia’s national oil company, it provides about two-thirds of the government’s revenue. It is the fourth largest company in the world by revenue, with a market value of about $1.7tn (£1.3tn) – roughly the same as the next five energy companies combined.

Aramco is not just the economic engine of Saudi Arabia but also plays a leading role in the kingdom’s efforts to rebrand itself on the global stage, notably through sports, where, as one of Fifa’s main sponsors, its name will be plastered all over this summer’s World Cup.

Aramco employs more than 76,000 people, but this figure hides a far larger number of workers employed through a long and complex chain of thousands of contractors and subcontractors. These workers, who are overwhelmingly migrant labourers from south Asia, may not show up in Aramco’s annual reports but they do the often difficult and dangerous work that drives its profits, from constructing its facilities to transporting its petrol.

Such an extensive labour supply chain does not exempt Aramco from its responsibilities to its entire workforce. The UN’s Guiding Principles on Business and Human Rights require companies to prevent human rights abuses “throughout their operations”. Aramco appears to accept this, stating online: “Aramco is committed to supporting and empowering our workforce and the communities where we operate. The safety and wellbeing of our employees, their dependents, and our company’s contractors is paramount to our strategy and operations.”

As a majority state-owned company, the UN’s guiding principles put additional responsibilities on the Saudi government “to ensure that relevant policies, legislation and regulations regarding respect for human rights are implemented”.

Now, Rauniyar is confined to a small room he rents in the south-east of Nepal.

Doctors have told him the bones in his right leg have not joined properly and he may need further surgery, but he says he does not have the money for it. “My legs hurt when I walk. I can’t lift weights. If my legs hadn’t been broken, I could have worked somewhere, but not in this condition,” he says.

Even before the accident, Rauniyar was struggling in Saudi Arabia. He says he was put to work on 10-hours shifts for just 1,000 rials a month (£200). “If we took a day off, they [the labour supply company] would deduct three days’ wages from our salary,” he says. He claims he was housed in overcrowded rooms “like pigs”, and his fellow workers fell sick because of the “rotten” food.

Now he relies on his wife’s meagre teaching salary of 7000 rupees (£35) a month and some fees from tuition classes he runs for local children. “We are poor. I don’t have a home. I don’t have anything. My life has collapsed,” he says.

FairSquare’s findings are consistent with reports from Human Rights Watch and the Business and Human Rights Resource Centre, which last year found evidence of rights abuses in Aramco’s labour supply chain. Severe labour violations were also uncovered at Aramco Stadium, the first new venue to be developed for the 2034 football World Cup. Earlier this year, the Guardian reported that the family of a Pakistani worker who fell to his death at the stadium was still waiting for compensation almost a year after his death.

Under Saudi law, when a worker is injured or dies in the course of their job, they or their family should receive compensation from a government insurance scheme or directly from their employer. Yet compensation was only paid out in one of the six cases of injury or death documented in FairSquare’s report.

Among those who failed to receive any compensation from Saudi Arabia is the family of Manjay Kumar Sah. When Sah gave his wife, Babita, a call early one morning in December 2023, there was no hint that the day would take a devastating turn. They would often have a quick chat, mostly to talk about their four young children.

After the call, Babita returned to work in the fields near her home on the southern plains of Nepal, while Sah set off for his shift as a scaffolder for a subcontractor on an Aramco project in eastern Saudi Arabia. As he waited at the work site to be assigned his work for the day, he suddenly collapsed. An ambulance was called, but Sah, 40, died shortly afterwards, a co-worker and relative told FairSquare.

Sah’s family was told by the subcontractor a postmortem would take three months, and so, still numb with grief, they agreed to bring his body home without one. Despite this – and a medical report stating “the cause of death is unknown” – Sah’s death certificate classified his death as “natural”. The term “natural death” is a catch-all used on the death certificates of many migrant workers who die in Saudi Arabia, but it provides no information about the underlying cause of death, suggests no in-depth investigation has taken place and allows some employers to avoid paying compensation.

Sah’s brother, who also worked in Saudi Arabia, told FairSquare no one was willing to take responsibility for his death or for compensation for his family. He said he asked the subcontractor’s supervisor dealing with the case about compensation many times, but he refused to listen. “Talk to your embassy. They’re the ones who settle it,” he claims he was told. The only compensation Sah’s family did receive came from insurance schemes in Nepal.

When news of her husband’s death reached Babita, she “fainted again and again. I was not even aware of what was happening,” she says. Two years later, Sah’s death still weighs heavy on Babita. “We’ve lost our breadwinner. Life has become very difficult,” she says. “We used to have many dreams for our children, but I’ve given up on them now.”

In a statement, Aramco said: “Safety and wellbeing is a core value of the company. Our project guidelines contribute to supporting safe working conditions and straightforward communication channels for raising concerns; and reflect our efforts to conducting business in an ethical, safe and responsible manner.” It said it had introduced a programme to “support the wellbeing of the contractor workforce”.

Saipem said it “takes the health and safety of all people involved in its projects very seriously and strives to act responsibly in every instance, including with regard to workers employed by contractors and subcontractors”.