LinkedIn forecasts weak first-quarter profit, shares plunge

LinkedIn Corp forecast first-quarter revenue and profit below Wall Street estimates as growth slows in its ads business and its hiring services face pressure outside North America, dragging its shares down 28 percent after the bell. Online ad revenue growth slowed to 20 percent in the fourth quarter from 56 percent a year earlier as automated ads offered by Alphabet Inc's Google make its traditional ad displays less attractive to advertisers. LinkedIn has been spending heavily on expansion by bu