Apple Inc. on Thursday defended against reports that its largest iPhone bends easily in people's pockets, saying warping is "extremely rare" through normal use.

Since going on sale Friday, Apple said only nine customers have contacted the company about a bent iPhone 6 Plus—the larger and more expensive of its two new iPhones. Apple said both the iPhone 6 and iPhone 6 Plus passed a series of tests meant to check the products' strength and durability through everyday use.

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