Friday was a positive day for the stock market, as investors celebrated the traditionally quiet day after Thanksgiving with solid gains. Sentiment among market participants has been positive throughout 2017, and with early holiday shopping activity showing little sign of any imminent change in that trend, the few investors who were trading in the holiday-shortened session today generally had an upbeat mood. There wasn't much news to move individual stocks, but a few companies did show good gains. SandRidge Energy (SD -0.61%), Advanced Semiconductor Engineering (ASX 0.48%), and Xunlei (XNET) were among the best performers on the day. Below, we'll take a closer look to see what made these stocks do so well.

SandRidge gets Icahn's attention

Shares of SandRidge Energy jumped 8% in the wake of news that activist investor Carl Icahn had become the energy company's largest shareholder. Icahn acquired a stake of more than 13% in the oil and gas producer, and the billionaire investor expressed his view that SandRidge should not go forward with a proposed merger to purchase Bonanza Creek Energy in a deal worth about $750 million. Other institutional investors also oppose SandRidge's move, arguing that the drain on cash would be dangerous for the company. SandRidge shareholders were already less than happy with the deal, but now they apparently think that Icahn could turn the tide and get the company back on track.

Large energy storage tanks with SandRidge logo on side.

Image source: SandRidge Energy.

Advanced Semi gets a key go-ahead

Advanced Semiconductor Engineering jumped 12% as the company received approval from antitrust regulators for its proposed merger with Siliconware Precision Industries (NASDAQ: SPIL). The combination had been in limbo for a long time, with antitrust authorities in different jurisdictions having looked at the merger for more than a year since the June 2016 initial announcement. The two companies now expect to complete the merger by May 2018, and they believe that the combined entity will be able to deliver enhanced services to its customers. For those who've liked Advanced Semi's prospects as an independent company, the future could be even brighter if this deal finally goes through. 

Xunlei keeps soaring

Finally, Xunlei finished higher by another 4%. The Chinese cloud computing company has gained a lot of attention recently in light of its decision to shift its strategic direction toward capitalizing on the success of blockchain technology. Although some have been skeptical about whether Xunlei actually has a viable vision or is simply trying to capture publicity by moving toward an area with higher demand, investors on the whole seem to believe that the company has a reasonable chance to be successful in its new business opportunities. Shareholders should expect volatility until Xunlei's long-term plans become clearer, but for now, excitement surrounding the stock is at an all-time high.