U.S. equities were trending lower early Thursday before recovering slightly later in the day, but most major indexes still finished the day mildly in the red. The S&P 500 Index fell 0.2%, while the Dow Jones Industrial Average gained a fraction of a percentage and the Nasdaq Composite dipped 0.2% by day’s end.

Several companies made headlines Thursday after the bell, including Activision Blizzard, Inc. (NASDAQ:ATVI), Arista Networks Inc (NYSE:ANET) and Twitter Inc (NYSE:TWTR).

Here’s what you should know ahead of Friday’s action:

Activision Blizzard, Inc. (ATVI)

Activision Blizzard shares fell after hours as the company posted mixed quarterly results, with earnings and revenue topping expectations, but its current quarter’s guidance missing the mark.

The video game studio announced adjusted earnings of 38 cents per share for its first quarter of fiscal 2018, which came in ahead of the 35 cents per share that analysts were calling for. Its revenue came in at $1.38 billion for the period, also ahead of the $1.32 billion that Wall Street called for in its consensus estimate.

Nevertheless, Activision Blizzard missed the mark with its second quarter, as the company projects that it will report earnings of 31 cents per share, compared to the consensus estimate of 47 cents per share. The company also forecasts revenue of $1.35 billion for the period, below the $1.45 billion from analysts’ outlook.

“As we look ahead, our innovative core gaming pipeline, as well as initiatives like mobile, esports, and advertising, will continue to drive growth for our business,” Activision Blizzard CEO Bobby Kotick said in a release. The company added that it will pay shareholders a dividend of 34 cents a share.

ATVI stock fell 0.2% Thursday after the bell.

Arista Networks Inc (ANET)

Arista Networks shares fell late yesterday despite the company unveiling better-than-expected quarterly results.

The company reported net income of $144.5 million for its first quarter, or $1.79 per share, which was stronger than its year-ago net income of $83 million, or $1.07 per share. On an adjusted basis, the company posted earnings of $1.66 per share.

Analysts were calling for adjusted earnings of $1.51 per share, according to data compiled by FactSet in their outlook. Arista Networks also brought in revenue of $472.5 million, a 40.83% gain compared to the $335.5 million it raked in during the year-ago quarter. The Wall Street consensus estimate called for revenue of $462.8 million, according to FactSet.

For its second quarter, the company is calling for revenue of $500 million to $514 million. Analysts are calling for Arista Networks to bring in revenue of $504.6 million.

ANET shares plummeted 8.5% after Thursday’s market close, despite the company’s earnings beat.

Twitter Inc (TWTR)

Twitter recently announced that the company was hit with a bug that could expose the passwords of all its users.

The social media site is calling on its more than 330 million users to change their passwords as soon as they can after the site was hit with a bug that exposed its users’ passwords in plain text.

Twitter’s investigation into the matter revealed that there was no evidence of a data breach or misuse of the unmasked passwords, but the company is still taking precautions by asking users to change their passwords.

Users should make this change both on the site and anywhere else they may have used the password, including third-party apps such as Twitterrific and TweetDeck. Twitter has not revealed how many passwords may have been revealed by this bug.

TWTR shares dipped 1.1% after hours yesterday.

As of this writing, Karl Utermohlen did not hold a position in any of the aforementioned securities.