US close: Vaccine optimism and corporate dealmaking boost sentiment

Wall Street stocks closed higher on Monday as a raft of corporate deals and optimism around a Covid-19 vaccine led a broad market rally.

At the close, the Dow Jones Industrial Average was up 1.18% at 27,993.33, while the S&P 500 was 1.27% stronger at 3,383.53 and the Nasdaq Composite saw out the session 1.87% firmer at 11,056.65.

The Dow Jones closed 327.69 points higher, extending gains recorded by the index in the final session of last week's volatile trading.

Sentiment got a slight boost from news that chipmaker Nvidia had agreed to buy competitor Arm Holdings from Japan's Softbank for $40.0bn - which it will finance through a combination of cash and common stock.

Also in deal news, TikTok parent ByteDance rejected Microsoft's bid to buy it US operations, opting instead to make Oracle its US partner, providing it with a significant stake in the business, while Gilead agreed to acquire Immunomedics as part of an effort to expand its cancer treatments.

On the earnings front, Miami-based homebuilder Lennar reported earnings of $666.4m after the close, up 30% year-on-year, as revenues remained broadly flat at $5.9bn.

News that AstraZeneca's UK vaccine trial had resumed following a halt to the study due to safety concerns provided stocks with a lift. However, the firm's US trials were still on pause as a result of the side effects presented in its British equivalent.

Pfizer chief executive Albert Bourla said over the weekend that the pharmaceutical giant's vaccine could very well be distributed across the US before the end of 2020.

As far as the coronavirus pandemic itself was concerned, the number of cases in 11 US states were growing by 5% or more, according to John Hopkins University.

In terms of ongoing stimulus negotiations on Capitol Hill, senate majority leader Mitch McConnell said late last week that the chances of both sides reaching an agreement didn't "look that good right now".