Recently Apple revealed that 90% of the iPhone and iPad chargers being sold on Amazon are counterfeit, according to this Forbes report. They are listed as “genuine” but these iPhone and iPad chargers are counterfeit, and I have had personal experience with that. Recently I purchased a charging data cable from Amazon and it was listed as genuine but just after a couple of uses it was easy to make out that it was not genuine but counterfeit.
As a result, Apple has filed a lawsuit against one of the major Amazon.com suppliers for the so-called genuine iPhone and iPad chargers, Mobile Star LLC, for trademark infringement.
To back up its claim, Apple purchased a number of iPhone and iPad chargers and discovered that most of the components were “poorly constructed, with inferior or missing components, flawed design, and inadequate electrical insulation.”
Through Amazon.com these iPhone chargers are being sold as genuine Apple products and some even have the Amazon Standard
Identification Number. The worst part is, during testing at the Apple Centre, many of the chargers caught fire due to faulty parts.
The above Forbes link also tells you how to know if the iPhone charger that you are purchasing from somewhere is actually genuine or counterfeit.
Of course big electronics companies carry out such operations also to make sure that spare parts are bought from them rather than from third-party sellers.