Tech stocks slide as Google faces renewed antitrust pressure

The tech-heavy Nasdaq Composite traded lower on Monday as Alphabet tumbled about 1% after 50 state attorneys general announced an antitrust probe into Google's ad business.

The news comes just days after New York Attorney General Letitia James said her office was coordinating a multistate antitrust probe into Facebook.

AT&T's stock price spiked as much as 5% on Monday after activist hedge fund Elliott Management announced a $3.2 billion stake in the company.

Oil surged to a six-week high after Saudi Arabia's new Energy Minister signaled OPEC and its allies would continue to lower outputs.

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The Nasdaq Composite, the most tech-heavy of the major US stock indexes, slid on Monday as shares of Alphabet tumbled as much as 1% following the announcement of new antitrust investigation into Google's ad business.

A coalition of state attorneys general from 49 states and Washington, D.C. announced the probe on Monday and said it will focus on whether Google has used anti-competitive practices in its ads business.

The announcement is the most recent advancement of antitrust scrutiny on large US tech companies. Shares of Facebook sunk last week after New York Attorney General Letitia James said her office was coordinating a multistate antitrust probe into the social media company.

On the macro front, Oil jumped to a six-week high after Saudi Arabia's new Energy Minister hinted OPEC and its allies might continue to lower output this year.

Here's a look at the major indexes as of the 4 p.m. close on Monday:

The S&P 500 fell 0.01%, to 2,978.43.

The Dow Jones Industrial Average climbed 0.14%, to 26,835.51.

The Nasdaq Composite slid 0.19%, to 8,087.44.

A jump in Treasury yields led a rally in bank stocks. Shares of JPMorgan rose 2.5%, Citigroup gained 4.3%, and Bank of America climbed 3.3%.

WeWork, which is expected to conduct one of the most highly-anticipated IPOs of the year, could cut its valuation below $20 billion, according a report from the Wall Street Journal. The company might also delay its IPO, the report found. WeWork's valuation has come under increased scrutiny in recent weeks due to questions regarding the company's ability to generate a profit.

Shares of AT&T surged as much as 5% on Monday after activist hedge fund Elliott Management announced a $3.2 billion stake in the telecommunications company. The firm said AT&T has a“ compelling value-creation opportunity,” and that it predicts shares could rise past $60 by the end of 2021. That would be a roughly 50% increase over current levels.

These were the biggest gainers in the Nasdaq 100 on Monday:

Walgreens Boots Alliance: 5.8%

NetApp: 5.4%

Mylan: 3.3%

And the largest decliners:

IDEXX Laboratories: 7.4%

MercadoLibre: 4.5%

Regeneron Pharmaceuticals: 4.5%

Within the S&P 500, gains in energy and financial stocks were offset by losses in real estate, healthcare, and technology.