DealBook Briefing: Is Facebook Headed Toward Its Darkest Timeline?

Good Tuesday morning. Here’s what we’re watching:

• Facebook had a terrible day.

• So did Uber.

• Leaders at the G-20 summit are still trying to avert a trade war.

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Facebook’s worst day in ages

Exhibit A: Its stock closed down nearly 7 percent, its worst performance in four years.

Exhibit B: Its chief security officer, Alex Stamos, plans to leave after disagreements about how much the company should share about misuse of its platform. (He favored disclosure.)

The overall problem: Reports about how the data firm Cambridge Analytica improperly harvested information from 50 million Facebook users are highlighting just how much governments itch to regulate the tech giant.

And Facebook’s previous laissez-faire attitude toward data collection by apps has gone from feature to bug, Kevin Roose writes in his latest column.

Peter Eavis’s take: Mark Zuckerberg’s unusually powerful position at the company may have played a role:

More on Cambridge Analytica: An undercover investigation by Channel 4 News of Britain captured the firm’s C.E.O., Alexander Nix, suggesting the entrapment of a potential client’s political opponents with women and bribes. Britain’s information commissioner is now seeking a warrant to examine the firm’s data. And Facebook has hired a forensics firm to audit it.

Critics’ corner

• Jeff Goldfarb of Breakingviews writes, “Ten years ago, Zuckerberg hired Sheryl Sandberg to help turn his start-up into a serious corporation. It may be time for more adult supervision.”

• The academic Zeynep Tufekci writes, “This wasn’t informed consent. This was the exploitation of user data and user trust.”

• Cass Sunstein of Bloomberg View writes, “It would be a mistake to take the fiasco as a reason to keep treasure troves of information out of the hands of people who can provide immensely valuable services with it.”

• Dan Gallagher of Heard on the Street writes, “Facebook’s immense scale also has made it virtually impossible for alternatives to catch on. That, in turn, makes abuse of the platform more urgent for lawmakers.”

Public service announcements: How to protect yourself on Facebook. Oxford Analytica, an advisory group, wants you to know it’s not like that. And a little joke for those steeped in the British university system:

A death that could set back self-driving cars

Uber has suspended its autonomous vehicle testing in four cities after a car in self-driving mode struck and killed a woman in Tempe, Ariz. Until now, regulators had been increasingly open to testing: Just this month, California said it would start letting self-driving cars operate without anyone behind the wheel. Arizona already had.

The head of Carnegie Mellon’s self-driving car lab has urged a halt to testing, telling Axios, “The technology is not there yet.”

The virtual currencies corner: The White House banned Venezuela’s virtual currency in a new round of sanctions. Morgan Stanley analysts said Bitcoin looked like the dot-com boom and bust, only way faster. How Zug, Switzerland, became a hotbed for digital money. And the Hong Kong and Australia stock exchanges are working to share blockchain information.

The tech flyaround

• Larry Ellison and David Agus, who was Steve Jobs’s doctor, have unveiled a start-up, Sensei, that promises more nutritious food through hydroponic farming. (DealBook)

• Europe’s plans to change how tech companies are taxed could exacerbate tensions with the U.S. (NYT)

• Amazon and Snapchat are chipping away at Google and Facebook’s digital ad duopoly. (The big two are still expected to control well over half the market in 2018.)

• Tech giants ask a lot of Wikipedia — see YouTube’s plans to use its text alongside controversial content — without always giving much back. (NYT)

• Amazon has reportedly considered buying Toys “R” Us stores, for the real estate. (Bloomberg)

• The Israeli historian Yuval Noah Harari worries that tech will transform humanity for the worse within decades. (NYT)

Foreign leaders are still trying to avert a trade war

Expect the White House to impose tariffs on some $60 billion worth of Chinese goods this week over what it says are unfair trade practices. But leaders at the G-20 summit meeting continued to push for free trade. More from Andrea Thomas and Paul Kiernan of the WSJ:

And some critics say that Mr. Trump is missing the bigger picture, including the U.S.’s trade surplus in services.

The budget corner: Lawmakers are still trying to finalize a $1.3 trillion spending bill ahead of Friday’s deadline. T hey disagree on health care and immigration.

The politics flyaround

• Gary Cohn as C.I.A. director? It was apparently considered. And the White House named Chris Liddell, the former Microsoft and G.M. executive, as deputy chief of staff for policy coordination.

• The White House added Joseph diGenova, a lawyer who argued the F.B.I. was out to get President Trump, to its legal team. Mr. Trump has also mused about whether to fire another lawyer, Ty Cobb, and a third, John Dowd, has considered resigning.

• Exploring why some Democrats voted for a Dodd-Frank rollback. (WaPo)

• The dangers facing the continued boom. (NYT)

• The Kochs urged Mr. Trump to accept the Democrats’ compromise on immigration. (Politico)

• The race to find loopholes in the new tax law. (WaPo)

• How that law may end up taxing sports teams’ player trades. (NYT)

Alwaleed bin Talal speaks out about his detention

Bloomberg interviewed the Saudi royal shortly after his release from the Ritz-Carlton, where Saudi Arabia detained hundreds of businessmen in the name of an anti-corruption campaign.

Mr. bin Talal wouldn’t comment on the deal for his release, but said that he has “forgiven and forgotten” the process, and continues to talk with Crown Prince Mohammed bin Salman, the cousin who jailed him. More from the interview:

Elsewhere in Saudi Arabia: Behind the bromance between Jared Kushner and the crown prince. Aramco looks increasingly likely to postpone an international listing, focusing on an I.P.O. on its home stock market, the WSJ says. And why the kingdom wants to enrich its own uranium.

Tronc’s chairman resigns ahead of misconduct allegations

Michael Ferro, who is also the media company’s biggest shareholder, stepped down hours before Fortune published an article in which two women accused him of inappropriate advances. Neither worked for him, but both said they had been interacting with him professionally. Mr. Ferro declined to comment on the allegations.

A recap of his tenure: Tribune became “Tronc.” Management opposed a newsroom unionization effort. The company sold its crown jewel, The L.A. Times, after controversies led to the replacement of senior executives.

Weinstein Company news: The troubled film studio finally filed for bankruptcy protection. And New York state is looking into how the Manhattan district attorney handled 2015 assault allegations against Harvey Weinstein.

Elsewhere in misconduct: A loose coalition of Silicon Valley companies like Airbnb, Dropbox and Stitch Fix are pressuring venture capital firms to diversify their ranks. Female employees at Nike circulated a survey about improper conduct by male colleagues. And a former employee of the celebrity chef Mike Isabella sued him for sexual harassment.

The deals flyaround

• The Long-Term Stock Exchange and IEX took a step to spread new standards for I.P.O.s. (DealBook)

• Boeing dropped its objection to Rockwell Collins’s sale to United Technologies. (WSJ)

• Bloom Energy has reportedly restarted its I.P.O. planning. (WSJ)

• Cheddar, the CNBC for the Snapchat generation, has raised $22 million from Raine Ventures, Liberty Global and the C.E.O. of the N.Y.S.E.’s parent company. (WSJ)

Revolving door

• Greenhill & Company has hired Neil Augustine from Rothschild as vice chairman and co-head of its of North American financing advisory & restructuring. (Greenhill)

• Germany has named Jörg Kukies, the co-head of Goldman Sachs’s operations in Germany and Austria, as its deputy finance minister. (FT)

• Paul Fishman, the former U.S. attorney for New Jersey, has joined the law firm Arnold & Porter as a partner and the head of its crisis management practice. (Arnold & Porter)

The speed read

• The S.E.C.’s chairman pressed exchanges to end a standoff that has delayed a massive database of stock and options trading. (WSJ)

• David Calhoun, a senior managing director at Blackstone, will give $20 million to Virginia Tech. (Bloomberg)

• Larry Fink finally threw his lot in with the machines. Will BlackRock’s algorithms beat the fund managers? (FT)

• The jewelry chain Claire’s has filed for Chapter 11 bankruptcy protection. (NYT)

• A case being tried before a National Labor Relations Board court could upend McDonald’s franchise business model by letting unions deal directly with the parent company — if it gets to a verdict. (NYT)

• A court fight in London between two Russian billionaires is testing the Kremlin’s patience. (Bloomberg)

• Federal prosecutors are investigating the fast-growing business of cash advances to plaintiffs in personal injury and other lawsuits, according to five lawyers. (NYT)

• British and E.U. negotiators agreed on the terms of a 21-month transition period to keep Britain inside Europe’s economic structures. It depends on a broader agreement on Britain’s withdrawal, which is by no means certain. (NYT)

• White boys who grow up rich are likely to remain that way. That’s not the case for black boys. (NYT)

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