There's a Downside to Making Parts for Apple

Apple sold 150 million iPhones last year, each carrying dozens of parts made by other companies. That’s why Apple is a perennial kingmaker among component manufacturers: Each time the company releases a model, some suppliers end up winners and others losers. Apple has a reputation as a brutally tough negotiator with companies in its supply chain, demanding advanced technology at razor-thin margins, and it doesn’t hesitate to drop longtime suppliers with little notice, says Francis Sideco, a senior manager at market researcher IHS. At least nine publicly traded companies get more than 40 percent of their revenue from Apple, data compiled by Bloomberg show.