IPhone Supplier Goes Stratospheric

Usually when a company's stock price more than doubles in six months, prospective investors might worry about piling in too late. Such prudence hasn't held back AMS AG, a small chipmaker based in Austria that's been catapulted to stock-market stardom as it gears up to supply Apple's new iPhones this fall.

Instead, AMS has become a rip-snorting exemplar of the euphoria gripping global semiconductors, as well as the power wielded by Apple over its suppliers. AMS shares rose 5 percent on Wednesday after Apple signaled that the new models would probably debut in September. With AMS expected to provide 3D sensing chips for the next iPhone, it says revenue will grow on average by 40 percent each year through 2019, to reach 1.5 billion euros ($1.8 billion).