For years, Samsung (NASDAQOTH: SSNLF) was the sole manufacturer of Apple‘s (NASDAQ: AAPL) A-series applications processors. However, beginning with the A8 system-on-a-chip, Samsung lost that business to Taiwan Semiconductor Manufacturing Company (NYSE: TSM).
Samsung would win back a portion of the follow-on A9 orders (Samsung and TSMC split those orders, and it is believed that Samsung received a majority allocation), but TSMC won the entirety of the A10 orders.
Image source: Apple.