Leaks about upcoming devices are common nowadays. While most leaks happen when certain “anonymous” sources “knowledgeable about the matter” speak to news sites, some leaks happen in different ways -- even to a company as serious about security as Apple.

According to an in-depth report from The Information, Apple started tightening up its security measures even more after the iPhone 5C was leaked to the public. It formed a security division that focused on keeping a very close watch over its suppliers and assembly partners in China, a country where a lot of knockoffs spring from out of nowhere like mushrooms after some rain.

The security division, called the New Product Security Team (NPS), was tasked to carefully monitor Apple’s factory workers and suppliers, and to seal up methods by which these people leak information about Apple’s new devices.

The report said that while the NPS grew to a team of more than 30 at one time, Apple eventually decided to move some of the monitoring work to contractors instead. These people were former U.S. military and intelligence operatives who spoke fluent Chinese.

Here are some of the things the NPS discovered and stopped while it closely monitored Apple’s Chinese workers and suppliers:

A tunnel

At one time, Apple caught workers secretly digging a tunnel behind a huge piece of machinery. The report cited a source saying "People were chipping away little by little at the wall 'Shawshank Redemption' style." The workers were hoping to use the tunnel as a way to smuggle components out from the facility to who knows where.

Unlikely places

The NPS also discovered some of the ways workers tried to smuggle valuable components out of factories. Some workers were caught hiding components in crawl spaces, tissue boxes, even used mop water and under discarded metal shavings. Some were also caught placing components in their shoes, belt buckles and bras.

Others

Despite Apple’s beefed-up security measures, though, some components still make their way out of factories. Apple, however, has established a way to locate the components and take them back, while discovering the source of the leak.

One such reported case is that of a business that teaches technicians how to repair damaged iPhone X glass screens -- even before the iPhone X was released. Apple discreetly enrolled a contractor in the class to determine the source of the leak.

Those who want to read the whole report can access it from The Information website.

Apple iPhone 5C
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