• Microsoft defends its deal to buy Call of Duty maker Activision Blizzard.
• Google's performance review system is getting tougher.
• James Cameron's "Avatar: The Way of Water" faces a big test at the box office.

Here are the most important news items that investors need to start their trading day:

1. Lumps of coal everywhere

It was the last trading day before Christmas, and all through Wall Street, barely a bull was stirring ... Ok, we're going to leave that there. Investors entered Friday a little bruised after Thursday's rough session. At one point, the Dow fell more than 800 points before a late-day push helped the blue-chip index finish down about 350 points. It was a particularly bad day for tech stocks, which dragged the Nasdaq down nearly 2.2%. With just five trading days left in December, stocks are on the cusp of finishing 2022 in the red, potentially wrapping up the worst year for equities since 2008. Read live markets updates here.

2. Microsoft pushes back

Microsoft officially responded to the Federal Trade Commission's attempt to block the software giant's $68.7 billion deal to buy video game maker Activision Blizzard. Microsoft, which produces Xbox gaming systems, contended that the acquisition wouldn't hurt competition and emphasized that it had made concessions to help get the deal approved. Regarding Activision's lucrative Call of Duty series, Microsoft said it had offered rival Sony, which makes PlayStation consoles, a 10-year deal to release the games for Sony systems on the same day they're offered for Xbox. "Sony refuses to deal," Microsoft said in its response to the FTC.

3. Google warns employees

Alphabet's Google told employees that more of them will be at risk of low performance ratings in 2023, according to internal communications obtained by CNBC's Jennifer Elias. The company estimates that its new evaluation system would put 6% of full-time workers into a category that carries higher risk for corrective action. It was 2% previously. The system will also make it harder for employees to score high marks. The changes come as the company grapples with its headcount after recent expansions. Executives have said there will be small cuts, and they haven't ruled out layoffs.

4. Moving back in with mom and dad

FTX founder Sam Bankman-Fried, the 30-year-old former crypto billionaire, is moving in with his parents in California. He has no choice. A federal judge granted the accused fraudster released on a $250 million recognizance bond under tight restrictions as he awaits trial on multiple criminal charges. Before he was arrested, and as his empire crumbled, Bankman-Fried said his personal fortune dwindled to about $100,000. So his bond was secured by equity in his family's home, as well as the signatures of his parents and two other people with "considerable" assets.

5. A big week for James Cameron and Disney

After a smaller-than-expected $134 million domestic opening weekend, director James Cameron's "Avatar: The Way of Water" faces a big test in its second week of release. Will it follow the pattern of the first "Avatar," which experienced small weekly dropoffs in business on its way to becoming the highest-grossing movie of all time? Or will it suffer the kind of second-week declines that plague the blockbusters of this era? The Disney sci fi epic does have a few things working in its favor: audience word of mouth has been good, and there's a general desire among moviegoers to see it in pricier premium formats like 3D and IMAX. Also, the week between Christmas Eve and New Year's is typically a big one for Hollywood, with kids home for the holidays and many people on vacation – and "Avatar" is the only big, family-friendly spectacle in town.

– CNBC's Samantha Subin, Jordan Novet, Jennifer Elias, Rohan Goswami, MacKenzie Sigalos and Sarah Whitten contributed to this report.

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