Thursday brought more good news for stock market investors, as major benchmark indexes climbed close to record territory. Investors continue to welcome friendlier talk on the trade front, and moves from the European Central Bank to offer a more accommodative monetary policy seemed to signal that the Federal Reserve might follow suit next week. In addition, some good news from companies in several different areas of the market improved the mood. Yelp (NYSE:YELP), LKQ (NASDAQ:LKQ), and Azul (NYSE:AZUL) were among the day's top performers. Here's why their shares did so well.

Yelp could get bought out

Shares of Yelp gained more than 5% on speculation that the company might get an acquired. Reports from The Wall Street Journal indicated that daily deal specialist Groupon (NASDAQ:GRPN) was looking to make a purchase, and that the online review pioneer could be its target. Yelp's stock has essentially gone nowhere during the past five years, and the company has found it challenging to come up with good ways to promote long-term growth. Moreover, it's heavily dependent on advertising-related revenue, which could leave it vulnerable in a recession. Yelp has made progress fundamentally in recent quarters, but some shareholders apparently hope that Groupon will give them a quick payday.

Yelp logo on top of a pile of different goods.

Image source: Yelp.

Activists look at LKQ

LKQ's stock rose 12% after an activist investor disclosed that it had taken a substantial stake in the auto parts company. ValueAct Capital revealed in a U.S. Securities and Exchange Commission filing  that it had purchased more than 5% of LKQ's outstanding shares, and the filing included typical language indicating its interest in discussing issues with LKQ management. For its part, LKQ  responded by acknowledging the filing and detailing some of its strategic efforts to boost shareholder value, including its 1 LKQ Europe initiative to integrate its European business more fully. LKQ management has predicted tough industry conditions ahead, and it looks as though ValueAct thinks it could help unlock value more quickly than the auto parts company could on its own.

Azul gets a new plane

Finally, shares of Azul ended the trading day up by more than 5%. The Brazilian airline said that it had taken delivery of its first Embraer 195-E2 aircraft, and expects the manufacturer to deliver five more by the end of the year. Azul currently has 51 firm orders for the model, which is more fuel-efficient and offers other upgraded features compared to the first-generation E195. CEO John Rodgerson said that Azul still faces a long process in switching more than half of its daily flights to newer aircraft, but Brazil's relative strength has made investors more comfortable about South American airlines broadly and Azul in particular.