Check out which companies are making headlines after the bell Wednesday:
Envision Healthcare Holdings - The provider of physician services posted fourth-quarter earnings per share of 4 cents on $984.8 million in revenue, versus estimates of 17 cents a share on $994 million in revenue. Its shares fell 2 percent in extended-hours trade.
Cardinal Health - Shares of the healthcare services provider gained 1.2 percent in after-hours trade after the White House said the Obama administration would allow people with insurance plans that don't comply with the Affordable Care Act keep them until October 2017, so long as their states permit.
Semtech - The analog supplier reported fourth-quarter earnings per share of 23 cents, excluding items, on revenue of $126.5 million. Analysts had estimated earnings of 23 cents a share on $125 million in sales. Its shares gained 1.6 percent in after-hours trading.
WuXi Pharmatech - The provider of medical outsourcing services reported fourth-quarter earnings per share of 53 cents on $157. 2 million in revenue. Analysts had estimated earnings of 43 cents a share on $156 million in revenue. Its shares fell 3.2 percent in after-hours trading.
—By CNBC's Kate Gibson
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