The deal would be the largest ever in the drug industry, valuing Botox-maker Allergan at around $150 billion. Because Allergan is based in Dublin, Pfizer could do a so-called “inversion,” moving its legal domicile to reduce taxes — following in the footsteps of Burger King, Medtronic and Mylan, which all inverted last year.

The Treasury is trying to stop the move, sending a letter to Congress saying it plans to issue new guidance later this week designed to cut tax benefits for companies that invert. It is unclear what effect that guidance may have on the Pfizer deal. The Treasury has said it can’t stop inversions without congressional action.

Republican candidates for President have proposed reducing the corporate tax rate, which at 39% is the highest in the world and driving the inversion trend. But Democrat Elizabeth Warren gave a speech yesterday attacking that argument, saying the tax code is filled with special breaks for corporations that make “the average effective tax rate for corporations is about the same” as in other developed countries.

More news below. Enjoy the day.

Top News

• Canadian Pacific sets groundwork for deal

Canadian Pacific touted the benefits of a possible combination with North American peer Norfolk Southern, saying a merger of the railroads would make them more efficient, result in tax savings and create a transcontinental network linking major North American industrial centers, cities and ports. So far, Norfolk Southern has responded in a lukewarm fashion to the takeover offer, though Canadian Pacific says it has only made an offer to talk – not a formal deal – essentially a call to get investors involved in the possible merger. ABC News

• Square pricing of IPO a bust

While there had been expectations that Square would price the payment technology company's initial public offering between $11 and $13 per share, on Wednesday evening the company raised a more modest $243 million by pricing the IPO at $9 per share, implying a market value of around $2.9 billion. It is a big disappointment for the company, which is expected to list this morning on the New York Stock Exchange under the ticker symbol “SQ.” None of Square's existing investors sold stock in the IPO, and the float represents just 8% of the company's outstanding shares. Fortune

• Sprint's deal angers T-Mobile's CEO

T-Mobile CEO John Legere is one of the more colorful executives on Wall Street – and we aren't just referring to the fact that he often features the company's hot pink in his wardrobe selections. His latest is a tirade involving rival Sprint – which launched a new "cut your bill in half" deal, targeting not just Verizon and AT&T and T-Mobile. Legere went on a tweetstorm, attacking Sprint's corporate troubles, claiming T-Mobile's network was faster than Sprint's, and promoting T-Mobile features like free video streaming. Fortune

• Starboard wants Yahoo to ditch spinoff

Activist investor Starboard Value LP is putting pressure on Yahoo to halt a planned spinoff of the company's stake in Alibaba Group, instead calling on it to sell its beleaguered Internet business. In a letter sent to Yahoo late Wednesday, Starboard said that a spinoff of more than $20 billion in shares of the Chinese e-commerce company carried too much risk. It is a pivot from last year, when Starboard called for a separation. Why the change? The federal government's decision not to rule on whether the spinoff would incur billions of dollars in taxes has cast a shadow over the plan. WSJ (subscription required)

• Fed: Economy could handle rate hike

The minutes of a late October meeting held by Federal Reserve policymakers revealed that most agreed the economy "could well" be strong enough next month to withstand the Fed's first interest rate hike in nearly a decade. The officials said global troubles had eased and a delay could increase market uncertainty and undermine confidence in the economy. That meeting summary provides the clearest evidence yet that a majority of the policymakers are leaning toward an increase next month. USA Today

Around the Water Cooler

• Tinder's parent sets IPO price

Online dating empire Match Group – which owns more than 40 online dating properties including Tinder, Match.com and OkCupid – has set the price of its initial public offering at $12 per share. That's the low end of the company's intended target range of $12 to $14, though Match is raising $400 million as it plans to start trading Thursday morning on the NASDAQ under the symbol "MTCH." Match, which has focused on the shift to mobile devices with its dating sites, is profitable and has been reporting strong revenue growth. Most of the company will continue to be owned by parent IAC/InterActiveCorp. Fortune

• Drug spending to reach $1.4 trillion by 2020

Global spending on drugs is expected to grow as much as 32% over the next five years, as the reach of medicines expands into emerging markets and because of greater use of pricier branded drugs in developed markets like the U.S. By 2020, more than half of the world's population will live in nations where medicine use will exceed one dose per person per day. While that increase seems staggering, the pace of spending growth will actually decline slightly from the prior five-year period, as greater use of generics has impacted pricing. Fortune

• The foods most likely to get you sick

Studies suggest that nearly one in 30 Americans – 10 million people – will get sick from a foodborne pathogen and as a result, the U.S. economy will take a $15 billion hit through lost income, lost revenue and health-care related costs. Which foods carry the most risk? Poultry, pork and other meats top the charts in terms of cost, though leafy vegetables are responsible for the greatest number of illnesses by a wide margin. Fortune

5 things to know today

Markets Surge and Square's Debut — 5 Things to Know Today. Today's story can be found here.