Broadcom Could Rise 20%

It’s too early to call the iPhone 7 a success, but there are signs that demand is running ahead of expectations. That’s obviously good news for Apple, whose shares are up 18% since the end of June. It also bodes well for key supplier Broadcom.

Until recently, the thinking on the semiconductor maker was that it can expand sales of its smartphone innards even in a sluggish environment for handset purchases, because Broadcom’s wares...