Intel, American Express among Friday’s biggest movers

These are the stocks making the biggest moves before the bell:
$Intel (INTC.US)$
— The chipmaker slumped more than 10% after issuing lower-than-expect first-quarter guidance.
$American Express (AXP.US)$
— Shares added 3% after the company issued full-year guidance that topped expectations, although its fourth-quarter results were weaker than expected.
$T-Mobile US (TMUS.US)$
— The telecommunications company declined 2% after posting mixed fourth-quarter results.