Last week, The Information's Wayne Ma reported about a sophisticated fraud scheme in which organized thieves would buy or steal iPhones, remove valuable components like the processor or logic board, swap in fake components, and return the purposefully-broken iPhones to receive replacements they could resell.

serial number reader

iPhone Serial Number Reader

Apple became aware of the increasing fraud in 2013 and, in the years since, it has managed to "dramatically reduce" the rate of iPhone-related repair fraud in its retail stores, particularly in China, according to the report.

One of Apple's countermeasures was to develop diagnostic software that its retail employees could use to quickly detect fake parts in iPhones, the report said. To evade this tactic, however, many fraudsters started to intentionally disable the iPhones so they couldn't be turned on and subjected to diagnostics.

Fraudsters even went as far as obtaining Apple customer records, including serial numbers, for iPhones that had already been sold in China. In some cases, the incorrect serial numbers would be etched on the back of the iPhones.

To combat the use of stolen serial numbers, The Information reported that Apple came up with a screening method known as "Zombie Check" internally that tested whether serial numbers for the broken iPhones held for inspection were also associated with iPhones still using Apple's online services like iCloud.

According to an internal Apple document obtained by MacRumors, the tool was initially limited to China, but Apple began rolling it out to Apple Authorized Service Providers around the world in February 2018.

The aptly-named Serial Number Reader is a simple tool with a Lightning connector on one end and USB-A on the other. It is used to validate the serial number of an iPhone 6 or newer that will not power on by retrieving it directly from the logic board, although a source said it doesn't always work.

To use the tool, a technician connects the end with the Lightning cable to the iPhone and the end with the USB cable to a Mac running macOS 10.8.5 or later. Then, the technician launches the companion Serial Number Reader app on the Mac and the iPhone's serial number should appear in most cases.

serial number reader macos
The tool can retrieve serial numbers from iPhones that have been damaged in a variety of ways, including units with a non-functional display. Liquid damage is also no obstacle, so long as the liquid is no longer leaking out of the device.

Apple's internal document states that "serial number validation ensures warranty and service eligibility associated with a serialized device is appropriately applied." The document adds that "validation ensures Apple only offers warranty service on genuine Apple products," thwarting fraudsters.

Apple's efforts appear to be working. Apple's annual Form 10-K indicates that, in 2017, Apple's warranty expenses decreased to $4.32 billion from $4.66 billion a year earlier. The serial number tool, it would appear, is quite effective.

Top Rated Comments

PBG4 Dude Avatar
92 months ago
“Decreased to $4.32 billion from $4.66 billion” is considered effective? Seriously?
Since when is saving $340 million dollars not a big deal?
Score: 13 Votes (Like | Disagree)
estabya Avatar
92 months ago
LMAO it uses USB-A. They can’t even get to their own USB-C future.
Score: 13 Votes (Like | Disagree)
Canyonero Avatar
92 months ago
Does anyone at Apple ever wonder if being so embedded in China is the way forward? It’s literally the place where they have to bend over backward for everything, including this. What if everyone just said no, enough. Play by the rules and until you do, we are not doing business with you. I know it’s too late for that now but did no one really think of this? Everyone just thought we are going to smooth sail to China, have them do our stuff for cheap and that’s it, they won’t try to benefit?
Score: 4 Votes (Like | Disagree)
alexksj Avatar
92 months ago
Considering that at the same time Apple increased their sales by 6% (215 to 229 bil $), this gives you an effective decrease of 13% of warranty costs in proportion to sales.

$340 million seems a lot in isolation, but when compared to a sum in billions that’s like a 7.3% reduction. It doesn’t really show how effective it is. This 7.3% reduction may just be the fact that warranty claims reduced due to increased reliability of the new phones. If it’s in the region of a 15% or more reduction, it will be more believable that it’s this device being effective.
Score: 4 Votes (Like | Disagree)
garoto Avatar
92 months ago
Since when is saving $340 million dollars not a big deal?
How can we attribute all the savings to that tool? Can it be that maybe fewer claims were made? Or that year over year, all claims made aren’t worth the same $, or that iPhones are more reliable?

I’m sure the tool helped, but all $340 million attributed to it? I guess possibly if year over year warranty claims kept increasing as more and more iPhones were sold, and since the tool was released, it was decreased.
Score: 3 Votes (Like | Disagree)
alleggerita Avatar
92 months ago
Since when is saving $340 million dollars not a big deal?
$340 million seems a lot in isolation, but when compared to a sum in billions that’s like a 7.3% reduction. It doesn’t really show how effective it is. This 7.3% reduction may just be the fact that warranty claims reduced due to increased reliability of the new phones. If it’s in the region of a 15% or more reduction, it will be more believable that it’s this device being effective.
Score: 3 Votes (Like | Disagree)

Popular Stories

ios 26 1 slide to stop

iOS 26.1 Brings Back 2007 Feature in New Way

Friday October 31, 2025 1:40 pm PDT by
The upcoming iOS 26.1 update includes a small but helpful change for iPhones, and it could prevent you from running late to something important. Specifically, when an alarm goes off in the Clock app, there is a new "slide to stop" control on the screen for turning off the alarm. On previous iOS 26 versions, there is simply a large "stop" button, which could be accidentally tapped. The new ...
M5 MacBook Pro

Waiting for New Macs? Apple Just Shared Bad News

Friday October 31, 2025 7:32 am PDT by
Apple has just given a strong indication that it will not be releasing any additional new Macs for the remainder of the year. Apple's CFO Kevan Parekh dropped the hint during the company's earnings call on Thursday:On Mac, keep in mind, we expect to face a very difficult compare against the M4 MacBook Pro, Mac mini, and iMac launches in the year-ago quarter.Parekh essentially gave a heads up ...
iPhone 17 Pro Cosmic Orange

8 Reasons to Wait for Next Year's iPhone 18 Pro

Thursday October 30, 2025 4:42 am PDT by
Apple's iPhone development roadmap runs several years into the future and the company is continually working with suppliers on several successive iPhone models at the same time, which is why we often get rumored features months ahead of launch. The iPhone 18 series is no different, and we already have a good idea of what to expect for the iPhone 18 Pro and iPhone 18 Pro Max. One thing worth...
iOS 26

6 New Things Your iPhone Can Do in iOS 26.1

Wednesday October 29, 2025 4:22 am PDT by
Apple is about to drop iOS 26.1, the first major point release since iOS 26 was rolled out in September, and there are at least six notable changes and improvements to look forward to. We've rounded them up below. Apple has already provided developers and public beta testers with the release candidate version of iOS 26.1, which means Apple will likely roll out the update to all compatible...
Coffee Burgundy and Purple iPhone 18 Pro Mock 1

Leaker Outlines Potential New Colors for iPhone 18 Pro

Friday October 31, 2025 8:28 am PDT by
Apple's iPhone 18 Pro models could be available in new rich and warm color option, according to a known leaker. The Weibo user known as "Instant Digital" today suggested that next-year's iPhone 18 Pro models will be available in at least one of the following color options: Coffee, purple, and burgundy. The iPhone XR, iPhone 11, iPhone 12, iPhone 14, and iPhone 14 Pro were all available in ...
Apple Foldable Thumb

iPhone Fold: Launch, Pricing, and What to Expect From Apple's Foldable

Friday October 31, 2025 8:52 am PDT by
Apple is expected to launch a new foldable iPhone next year, based on multiple rumors and credible sources. The long-awaited device has been rumored for years now, but signs increasingly suggest that 2026 could indeed be the year that Apple releases its first foldable device. Below, we've collated an updated set of key details that have been leaked about Apple's foldable iPhone so far. Ove...
apple tv hd

Apple Launched Its Big New Vision for TV 10 Years Ago Today

Thursday October 30, 2025 8:58 am PDT by
Apple launched the Apple TV HD, the Siri Remote, tvOS, and their accompanying App Store a decade ago today, marking a major overhaul of the device. The new vision for the Apple TV was unveiled on September 9, 2015 during Apple's "Hey Siri" event in San Francisco, where CEO Tim Cook introduced the device with the statement, "The future of TV is apps." The announcement represented a major...
iOS 26

Apple This November: iOS 26.2 Beta, Rumored New Products, and More

Thursday October 30, 2025 12:42 pm PDT by
Tomorrow is Halloween, and then November is upon us. Below, we outline what to expect from Apple next month, as the slower holiday season approaches. Apple is expected to kick off November by releasing iOS 26.1, iPadOS 26.1, macOS 26.1, watchOS 26.1, tvOS 26.1, and visionOS 26.1. With beta testing now wrapped up, the updates will likely be released this Monday, November 3 or Tuesday,...
iOS 26

iOS 26.1 Coming Soon: New Features for Your iPhone and Release Date

Monday October 27, 2025 7:55 am PDT by
The upcoming iOS 26.1 update includes a handful of new features and changes for iPhones, including a toggle for changing the appearance of the Liquid Glass design, "slide to stop" for alarms in the Clock app, and more. Below, we outline key details about iOS 26.1. Release Date Given that Apple has yet to seed an iOS 26.1 Release Candidate, which is typically the final beta version, the...
iOS 18 Siri Personal Context

Apple CEO Tim Cook Says Revamped Siri on Track to Launch Next Year

Thursday October 30, 2025 1:50 pm PDT by
Apple CEO Tim Cook today said that a more personalized version of Siri remains on track to launch at some point next year, with the new set of features expected to debut on the iPhone as part of iOS 26.4 in March or April. "We're also excited for a more personalized Siri," said Cook, on Apple's earnings call for the third quarter of the 2025 calendar year. "We're making good progress on it,...