If your heart is still pounding from a bracket-blowout weekend of NCAA basketball, then you’re all set for what Wall Street could be ready to dish out today.

Tech stocks — which have done some heavy lifting for markets this year so far — are having a bumpy ride today. (See more on that tech leadership in our chart of the day below)

Blame Facebook FB, -1.73% , looking at its worst daily decline in more than three years, and pulling lots of tech names lower after it revealed late Friday that a firm linked to the 2016 Trump election campaign amassed data from millions of its users without their permission. Clearly investors are getting nervous as U.K and U.S. lawmakers sound the regulatory sirens.

Weighing in on this, our call of the day from Raoul Pal, Global Macro Investor founder, says Facebook and Google-parent Alphabet’s GOOGL, -1.44% stock may be nearing a critical moment.

“I’m wondering whether we are fast approaching the tipping point for $FB and $GOOGL’s fall from monopolistic power, as global regulators begin to take notice as to all the (inadvertent?) inappropriate behavior that has taken place. The short-selling case is building fast ...” says Pal in a post to Twitter on Sunday.

As a reminder, short selling by definition is driven by a belief that an asset is set for a fall.

Pal’s comment kicked off a lengthy Twitter discussion on the topic, including this from Dee Smith, who predicts a “game-changing shift” over personal data.

“And as this accelerates, and individuals assert ownership of their own information, it will dramatically change the fundamental business proposition of internet [companies],” says Smith, who describes himself as CEO of Strategic Insight Group

Pal notes that he was definitely bullish on Alphabet and Facebook once, saying “data is and was the new oil, but like Standard Oil, they are now entering a riskier phase.”

The chorus of concern is building. Last week, “father of the World Wide Web” Tim Berners-Lee himself called for a regulatory crackdown on the giants of the internet.

Investors have been showing a preference for younger tech players, with Facebook up just 4% year to date and Twitter TWTR, -0.62% leaving that elder internet statesman in its dust with a 48% climb so far. It’s definitely a rough start to the week.

Key market gauges

The Nasdaq COMP, -0.13% is getting hit fairly hard this morning. The Dow DJIA, -1.84% and S&P 500 SPX, -1.15% are also down. Remember it’s Fed-meeting week, with most looking for an interest-rate hike. The Nikkei NIK, +0.17% bucked a mostly upbeat session for Asia, as a land-sale scandal continues to dog PM Shinzo Abe. Europe stocks SXXP, -3.24% are down along with Wall Street.

Read:The Fed needs ‘an acrobatic sense of balance’ to keep markets calm

The dollar DXY, -0.13% is dropping and part of that comes as the U.K. pound GBPUSD, +0.03% has rallied after the EU and U.K. agreed a Brexit transition deal. Gold US:GCJ8 has flattened out, while oil prices US:CLJ8 are falling.

Read:The pound could surge in ‘frenetic’ week of Brexit, BOE news

Keep an eye on this week’s G-20 finance ministers meeting in Buenos Aires, where the “key discussion theme will be trade relations between the world’s stronger economies,” says ADS Securities researcher Konstantinos Anthis.

Check out Market Snapshot for more on today’s action.

The quote

Andrew McCabe, former acting director of the FBI, who has been sacked. Getty Images

“If anyone in the current administration or associated with it were held to the standard FBI agents are in OPR, there would literally be no one left in the Executive Branch.” — That was former FBI Special Agent Asha Rangappa.

She was reacting to a tweet from political analyst Britt Hume, who said the firing of FBI Deputy Andrew McCabe — let go two days before he was set to retire — was a no-brainer.

OPR stands for FBI agent watchdog the Office of Special Responsibility, which recommended McCabe’s dismissal, carried out by Attorney General Jeff Sessions.

See:Political-risk gauge just hit a 15-year high — here’s what it means for stocks

And check out:Trump dismisses memos that McCabe reportedly wrote after meetings

The chart

The stock market has a leadership problem — as in there aren’t enough of ‘em.

That’s what Jonathan Krinsky, chief market technician at MKM Partners, is telling clients in his latest note. The S&P is down 4.21% since its all-time high on Jan. 26 (but many stocks are down more than that) and the median stock is around 9% below its 52-week high, he notes.

“This raises the question, aside from technology, where is the leadership?” asks Krinsky.

Here’s his chart that shows how the information technology sector (identified in green) is all alone in that leadership role:

The buzz

Newell Brands NWL, -3.55% is getting a boost after a cooperation deal with activist investor Carl Icahn.

In a first, Apple AAPL, +3.03% is making its own display screens, reports Bloomberg. Here’s three ways the iPhone maker could spend $163 billion in cash, as promised. It’ll be worth looking to see if the Asian suppliers take another hit on Tuesday morning.

Retailer Claire’s has filed for bankruptcy.

Bitcoin BTCUSD, -0.15% cratered late Sunday, but then rallied about $700 to get back above $8,000. That was all down to a report that Twitter TWTR, -0.62% may follow Google and Facebook in banning cryptocurrency ads.

If Tesla TSLA, +1.63% is too pricey or popular for you, then check out this European electric-car-related stock that’s well off the radar right now.

Democrats now have a double-digit edge over Republicans when it comes to midterm elections, says new poll.

It’s going to be a fairly quiet week on the data front. But that’s probably a good thing, given we’ve got the FOMC’s two-day meeting, which concludes Wednesday. Still, here’s why it’s worth keeping an eye on one piece data — business inventories — this week.

Read:What to expect from the new Fed dot plot on interest rates

Plus:The Fed needs ‘an acrobatic sense of balance’ to keep markets calm

The stat

Florida State Seminoles take out Xavier Musketeers over the weekend. USA Today Sports

Four — that’s how many of this week’s Sweet 16 NCAA basketball games will involve a No. 1 or No. 2 seed after a weekend full of upsets. University of Maryland-Baltimore County, seeded 16, beat No. 1 seed Virginia Cavaliers, and a chunk of the top-ranked teams have failed to advance. That means all the March Madness brackets have been officially busted.

Random reads

After a string of deadly package bombs, another explosion injures two in Austin

Trump ready to crack down on opioid abuse, wants death penalty for traffickers

18 years at the helm and going strong. Russian President Vladimir Putin aces another 6-year term

A homage to homeless hacker Adrian Lamo, who recently died at 37

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