S&P 500 slides on California reopening rollback after briefly erasing post-COVID losses

• US stocks slid on Monday, erasing earlier gains, as the governor of California announced closures of bars and indoor dining, spurring worries around economic reopening nationwide.
• The S&P 500 jumped as much as 1.6% and briefly erased its year-to-date losses before turning negative in the afternoon.
• Pfizer and BioNTech gained jumped after two of the firms' COVID vaccine candidates received "fast track" status from the FDA.
• Oil fell amid fears of OPEC+ unwinding production curbs. West Texas Intermediate crude dropped as much as 2.7%, to $39.47 per barrel.
• Watch major indexes update live here.

US stocks slid on Monday, erasing earlier gains, as the governor of California extended closures of bars and indoor dining, spurring worries around economic reopening nationwide.

The S&P 500 started the day strong, briefly erasing post-virus losses, before retreating in the afternoon as new reopening concerns surfaced. The tech-heavy Nasdaq Composite index — which is fresh off a series of record closes — tumbled more than 2%.

On the corporate earnings front, PepsiCo jumped after revealing better-than-expected revenue in the second quarter. The report marked the unofficial start of an earnings season set to be more chaotic than usual.

Several companies pulled forward guidance in their previous reports, citing uncertainties sourced from the coronavirus pandemic. Investors now wait to see which corporate giants outperformed and which faltered throughout widespread lockdowns.

Here's where US indexes stood at the 4 p.m. ET market close on Monday:

• S&P 500: 3,155.22, down 0.9%
• Dow Jones industrial average: 26,085.80, up 0.1% (11 points)
• Nasdaq composite: 10,390.84, down 2.1%

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Major banks kick off earnings season on Tuesday, with JPMorgan, Citigroup, and Wells Fargo all slated to release quarterly results. The firms are expected to show a sharp decline in profits due to bolstered loan-loss reserves and weakened net interest income.

"The market has been consolidating for the past few weeks but earnings could provide the spark needed to break it of its range," Chris Larkin, managing director of trading and investment product at E-Trade, said. "With banks up first, themes that emerged last quarter may likely be amplified—loan losses driving the downside, with increased trading revenue a potential bright spot."

In deal news, Maxim Integrated Products leaped after rival firm Analog Devices said it would purchase the firm in a $21 billion all-stock deal. The takeover is among the year's largest.

Tesla shares rocketed as much as 16% to a fresh record after announcing the date for its Battery Day event. The automaker is expected to unveil a battery capable of lasting for one million miles and further extend its lead over rival companies. Tesla erased all of its intraday gains and finished 3.1% lower.

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Pfizer and BioNTech gained after two of the firms' coronavirus vaccine candidates received "fast track" status from the Food and Drug Administration. Both companies have said they plan to produce as many as 100 million doses by the end of 2020 if their vaccine gains regulatory approval. A trial with up to 30,000 participants can begin as soon as later this month, they added.

Elsewhere in the biotech sector, Moderna surged as much as 24% after the Nasdaq exchange placed the company in its 100-stock index. Jefferies added fuel to the rally, initiating a "buy" rating on the biotech stock and setting a $90 price target. The level implies a 45% jump from its Friday close.

Read more: A Wall Street investment chief dispels the notion that surging stocks are disconnected from the economy — and lays out 3 reasons why the market will continue to climb over the next year

Oil declined amid fears of OPEC+ retracing production cuts in its Wednesday meeting. West Texas Intermediate crude slid as much as 2.7%, to $39.47 per barrel. Brent crude, the international benchmark, fell 2.3%, to $42.24 per barrel, at intraday lows.

The stock market's gains follow a positive close to the previous week. Equities climbed roughly 1% on Friday as investors cheered a different coronavirus vaccine candidate. Gilead Sciences announced trial data for its remdesivir compound found a 62% reduction to mortality risk among severe COVID patients. Banks including Goldman Sachs, Wells Fargo, and Citigroup also jumped through the session.

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