Market Insider

Stocks making the biggest moves after hours: AMD, EXAS & more

People walk by the New York Stock Exchange (NYSE) on December 19, 2017 in New York City.
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Check out the companies making headlines after the bell Thursday:

Advanced Micro Devices shares fell more than 2 percent in the extended session. Just over a week after claiming its chips were at " near zero" risk for a security flaws impacting Intel chips, the semiconductor company has changed its tune. A Thursday announcement revealed two of the three exploits are applicable to AMD processors.

Intel shares edged up slightly after the bell.

Exact Sciences stock plunged about 5.6 percent in extended trading. The molecular diagnostics company announced it would offer $500 million in convertible senior notes. Bank of America Merrill Lynch will act as the sole bookrunner. Exact Sciences intends to use net proceeds for general purposes, including funding commercialization of colorectal cancer diagnostic
test Cologuard, Thomson Reuters reported.

Exact Sciences also released fourth quarter financial guidance.

Finisar stock climbed more than 2 percent after the bell. The communications equipment producer announced the retirement of co-founder and EO Jerry Rawls. Former Broadcom executive Michael Hurlston will replace Rawls as CEO.

Broadcom shares dipped slightly.

Shares of IBM dipped slightly in extended trading, before recovering. The multinational technology company announced Senior Vice President and CFO Martin Schroeter will step down as Chief Financial Officer and into a role as Senior Vice President of Global Markets. He will be replaced by Senior Vice President of Finance and Operations James Kavanaugh.