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Here's Who's on Apple's Supply Chain

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NEW YORK ( TheStreet) -- Apple's supply chain is notoriously complex and growing ever larger. This comes as the company sources parts from vastly different regions, to keep selling as many iDevices as possible.

The company first unveiled its supplier list uin 2011, as part of a release concerning environmental issues at plants in China. There are obvious names among the 33-page list for 2013 , including companies such as Qualcomm , Intel , Avago Technologies , Hon-Hai Precision Industry (Foxconn) and others, but there are several names included on the list that may not necessarily be thought of as associating with Apple.

Companies such as Alcoa (who knew?!?!), R.R. Donnelly & Sons and BYD, the Chinese auto maker are also on the list.

When the list first appeared in early 2012, the name that stood out to me was NXP Semiconductor , which makes chipsets designed for near field communications (NFC) use. NFC technology allows customers to pay for devices with their phones instead of cash or a credit card, simply by tapping their phone to a reader.  The phone is linked to the person's bank account and the transfer is made.

Apple has not included NFC capabilities on its iPhone or iPad yet, but has introduced the Passbook app, Touch ID, and iBeacon, all of which are designed potentially to help with the payments ecosystem, along with location-based advertising and deals.

Given how complex Apple's supply chain is, it's tough to read into what each of these companies could be doing with Apple. CEO Tim Cook made comments on Apple's Jan. 23, 2013 earnings call discussed the supply chain: "I would suggest it's good to question the accuracy of any kind of rumor about build plans and also stress that even if a particular data point were factual it would be impossible to accurately interpret the data point as to what it meant for our overall business because the supply chain is very complex and we obviously have multiple sources for things, yields might vary, supply performance can vary."

"The beginning inventory positions can vary, I mean there is just an inordinate long list of things that would make any single data point not a great proxy for what's going on," Cook added.

The company that stands out the most to me is BYD. Apple introducing iOS for the car at its Worldwide Developers Conference (WWDC) in June. Auto manufacturers such as BMW, Honda , Mercedes-Benz, Infiniti and Jaguar already have deals to bring iOS integration into some of their models.

BYD has other segments, and its IT business segment counts cell-phone companies such as Nokia, Motorola, Samsung and others as major customers. Perhaps this is where Apple fits in.

Are there any companies you're surprised about seeing on the list?