By Joe Wallace
U.S. stocks rose on Monday, as a rebound in technology shares lifted major indexes following a sharp pullback last week.
The S&P 500 advanced 1.6% in morning trading. The Dow Jones Industrial Average climbed 334 points, or about 1.2%.
The tech-heavy Nasdaq Composite jumped 2.1%. Last week, the Nasdaq suffered its biggest one-week decline since March's market crisis.
Oracle was among the strongest performers in the S&P 500, with shares climbing 4.3% after the tech company won the bidding for the U.S. operations of video-sharing app TikTok, according to people with knowledge of the matter. Chip maker Nvidia rallied 8.3% after it agreed to buy British chip-designer Arm Holdings for more than $40 billion from SoftBank Group Corp.
Monday's advance extends a spell of outsize moves in both directions for global markets. Stocks have been buffeted by uncertainty about the U.S. presidential election, a slowing recovery in the world economy from the shock of Covid-19, and gyrations in tech shares that had driven markets higher since the spring.
"We're shifting into an environment of lower returns and higher volatility and this is not inconsistent with that," said James McCormick, global head of desk strategy at NatWest Markets.
"This isn't a message that we're going back to February, March markets," Mr. McCormick added, referring to the historic declines that took place when countries locked down to control Covid-19. "But I think the upside is going be a bit capped here until we get through some of these events and risks."
Investor sentiment was boosted by the resumption of clinical trials of AstraZeneca's experimental coronavirus vaccine in the U.K., analysts said. Studies were put on pause globally after a person who received the vaccine had an unexplained illness. Trials in other countries, including the U.S., remain on hold.
"There's a bit more positivity as regards vaccines," said Robert Carnell, head of research for Asia-Pacific at ING Groep. "The resumption of AstraZeneca trials will be seen in that light."
All 11 sectors of the S&P 500 advanced, with the tech sector leading the way with a 2.2% gain.
In corporate news, investors appeared to welcome news that ViacomCBS is close to selling CNET Media Group to Red Ventures, pushing Class B shares in the entertainment giant up 1.3%.
Gilead Sciences slipped 1.4% after the pharmaceutical company said it would pay $21 billion to buy biotech Immunomedics and its prized breast-cancer drug.
In government bonds, the yield on 10-year Treasury notes slipped to 0.664%, from 0.668% on Friday. Traders are awaiting the conclusion of the Federal Reserve's two-day monetary-policy meeting Wednesday, when the central bank is expected to hold interest rates steady.
The WSJ Dollar Index, which tracks the U.S. currency against a basket of others, fell 0.4%.
U.S. crude-oil prices fell 0.2% to $37.26 a barrel. In a monthly report, the Organization of the Petroleum Exporting Countries said the pandemic would reduce global oil demand by around 9.5% this year, more than the cartel previously forecast.
International stock markets were broadly higher. The Stoxx Europe 600 ticked up 0.2%. In Asia, China's Shanghai Composite Index closed up 0.6% and Japan's Nikkei 225 advanced 0.7%.
Among individual European stocks, Euronext fell 3.3% after the pan-European exchange operator said it had submitted an offer to buy Borsa Italiana from London Stock Exchange Group.
Write to Joe Wallace at Joe.Wallace@wsj.com