KEEPING SCORE: The Dow Jones industrial average jumped 97 points, or 0.5 percent, to 18,337 as of 12:40 p.m. Eastern time. The index rose as much as 159 points earlier. The Standard & Poor’s 500 index rose 11 points, or 0.5 percent, to 2,164. The Nasdaq composite added 41 points, or 0.8 percent, to 5,333.
ENERGY: Benchmark U.S. crude rose $1.33, or 2.7 percent, to $51.14 a barrel in New York while Brent crude, used to price international oils, gained $1.13, or 2.2 percent, to $53.06 a barrel in London. Exxon Mobil climbed $1.56, or 1.8 percent, to $88.30 and Murphy Oil added 64 cents, or 2.2 percent, to $30.16.
SHOT IN THE ARM: Drugmaker Mylan gained $3.11, or 8.7 percent, to $39.05. On Friday the company agreed to pay $465 million to settle allegations it overcharged the Medicaid program for its EpiPen allergy shot. Legislators and federal health authorities had said Mylan wrongly classified EpiPen as a generic drug instead of a brand-name one, which meant Mylan paid lower rebates to federal and state Medicaid programs. The stock is down 20 percent since late August.
BRISTOL BUMPED: Bristol-Myers Squibb lost $5.55, or 10 percent, to $49.89 after the company reported new data from a study of its drug Opdivo in lung cancer patients. Rival Merck rose $1.13, or 1.8 percent, to $63.91 as investors were pleased with the outcome of a study of its cancer treatment Keytruda. Bristol-Myers stock has dropped 34 percent since the company announced initial results from that trial in early August while Merck has gained 10 percent.
TWITTER BLOCKED: Social-media network Twitter continued to fall as investors grew less optimistic that the company will be sold. Twitter sank $2.67, or 13.5 percent, to $17.18. It fell 20 percent Thursday on reports that possible buyers including Apple and Alphabet had decided not to make offers. Salesforce.com, which investors believe is a possible buyer, rose $4.25, or 6 percent, to $75.16.
SAMSUNG’S PAIN, APPLE’S GAIN: Apple climbed $2.24, or 2 percent, to $116.30 as investors hope it will be able to sell more iPhones as competitor Samsung faced new problems with its Galaxy Note 7. Samsung said it has changed its production of the phones following reports that some of its replacement phones are overheating and catching fire, just as the original version of the phone did before Samsung recalled it last month. Samsung did not confirm or deny a report from a Korean news agency that it suspended production of the Note 7 phone.
PESOS AND PRESIDENTS: The Mexican peso surged to 18.8815 from 19.2961 following a calamitous weekend for Republican presidential candidate Donald Trump. Trump has criticized Mexico and its trade agreements with the U.S., so the peso has become something of an indicator of how investors feel about the election. The currency has tended to weaken when investors feel Trump is doing better and gets stronger when investors feel more confident in Democratic candidate Hillary Clinton’s chances.
The U.S. buys about 80 percent of Mexico’s exports, which gives it a big influence on the Mexican economy. The peso has fallen sharply this year but is currently the strongest it’s been in about a month.
DOVER DIVES: Manufacturer Dover forecast a smaller profit and a bigger decline in revenue because of weaker spending in several industries and production problems in its retail refrigeration unit. The company also said its purchase of British company Wayne Fueling Systems won’t close until early next year because regulators in the United Kingdom are still reviewing the deal. The stock gave up $4.93, or 6.8 percent, to $67.31.
OVERSEAS: Germany’s DAX rose 1.3 percent and the CAC-40 in France was 1.1 percent higher. The FTSE 100 in London rose 0.8 percent. The Kospi in South Korea rose 0.1 percent. Japan’s markets were closed for a holiday.
CURRENCY: The dollar rose to 103.66 yen from 103.06 yen Friday. The euro fell to $1.1152 from $1.1182, and the British pound fell to $1.2383 from $1.2435. Bond trading was closed for the Columbus Day holiday.