Check out the companies making headlines after the bell Thursday:
Software maker Red Hat beat on the top and bottom lines with earnings of 44 cents a share on $481 million in revenue. That compares to estimates of 41 cents on $473 million in sales. Still, shares fell 1 percent after hours as earnings guidance came in slightly lower than expected.
Jana Partners disclosed a 7.2 percent stake in ConAgra Foods and called the grocer's shares undervalued, according to a regulatory filing. ConAgra shares jumped about 6 percent on the news.
Shares of electrical components maker Finisar rose more than 1 percent after it reported an 8.1 percent increase in full-year revenue.
Firearm manufacturer Smith & Wesson topped fourth-quarter earnings and sales projections, but provided a soft first-quarter outlook. The stock tumbled about 4 percent.
Shares of Sequential Brands, which operates a portfolio of lifestyle brands, rose about 13 percent during the regular session on reports that it was near a deal to acquire Martha Stewart Living. It briefly turned lower after the bell and then returned to flat. MSO shares jumped some 26 percent during the regular session and climbed more than 2 percent in extended trade.