Check out which companies are making headlines after the bell Wednesday:
Google - The Internet-search engine posted first-quarter earnings of $6.27 a share, excluding items, on $15.42 billion in revenue, versus estimates calling for EPS of $6.41 on $15.54 billion in sales. Its shares fell 5.8 percent in after-hours trading.
Facebook - The social-networking site fell, along with other momentum names, including Priceline Group, Amazon.com, Tesla Motors and Netflix.
American Express - The card issuer reported per share of $1.33 on $8.20 billion in revenue, versus estimates calling for EPS of $1.30 on $8.36 billion in sales. Shares declined 1.5 percent in after-hours trading.
SanDisk - The memory chipmaker reported earnings per share of $1.44, excluding items, on $1.51 billion in revenue. Analysts expected first-quarter revenue of $1.49 billion. Its shares rose 2.3 percent.
Capital One - The credit card issuer tallied first-quarter earnings per share of $1.96 on $5.37 billion in revenue. Analysts expected EPS of $1.69 on sales of $5.44 billion. Its shares climbed 0.6 percent.
IBM - The technology company tallied first-quarter earnings of $2.54 a share, excluding items, on $22.48 billion in revenue, versus expectations of EPS of $2.54 on $22.91 billion in sales. Its shares fell 4 percent in after-hours trading.
—By CNBC's Kate Gibson
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