Apple has accused a number of suppliers of violating its labour and environmental policies after conducting an audit, according to Reuters.
On Wednesday, the American tech giant said that a minority of its suppliers are ignoring its code of conduct. For instance, the firm caught some of them forging work hours data.
Every year, the company runs an audit of the companies and workers responsible for making popular devices such as the iPhone, iPad and Macbook.
The company works with around 756 suppliers in 30 countries, although the majority of them have been complying to Apple's rules to a satisfactory standard.
After republishing a report summarising the audit, the company revealed that there were fewer 'low performers' in 2017. The number of suppliers in this category decreased by one per cent, compared to three per cent in 2016.
To fit in this category, the supplier needed to score less than 59 out of 100. However, the amount of "high performers" grew by 59 per cent - a record high for the firm.
Overall, the company's auditors identified 44 "core violations", more than double compared to the year before. They found three cases of suppliers charging employees to work for them.
In 2015, Apple updated its code of conduct to clamp down on this practice. An Apple supplier based in the Philippines made prospective employees pay $1 million to secure a job at the firm, but it has since been ordered to repay the money.
The company's code of conduct also takes a strict stance on work hours. Normally, it expects suppliers to work 60 hours a week producing Apple products.
But the report shows that there were 38 instances of suppliers making up their work hours data to fraudulently comply with the rules. These companies were expected to undergo a probationary period.
In a bid to promote diversity among its suppliers, the company explained that it is also developing a women's health programme to support employees.
Jeff Williams, COO of Apple, said the company wants "everyone making Apple products deserves to be treated with dignity and respect".
He added: "We're proud that almost 15 million people understand their workplace rights as a result of the work we've done over the years.
"We're going further with health education programmes and new opportunities for advancement at our suppliers."
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