• Home
  • Latest
  • Fortune 500
  • Finance
  • Tech
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
Finance

Wall Street Is Betting the Pfizer-Allergan Deal Won’t Happen

By
Jen Wieczner
Jen Wieczner
Down Arrow Button Icon
By
Jen Wieczner
Jen Wieczner
Down Arrow Button Icon
April 5, 2016, 3:41 PM ET
Pfizer Inc. Headquarters As They Agree To Combine With Allergan Plc In $160 Billion Deal
Photograph by Bloomberg via Getty Images

The way their stocks are trading, it’s as if Pfizer never even met Allergan—let alone struck a $160 billion deal last year to do the largest merger the pharmaceutical industry has ever seen.

Allergan’s shares plunged more than 16% on Tuesday, after the U.S. Treasury Department proposed new rules to limit so called tax inversions—deals in which American corporations acquire a foreign company and then reincorporate overseas for the primary purposed of lower their tax bill.

Pfizer is reportedly considering abandoning the deal. Officially, Pfizer (PFE) and Allergan (AGN) jointly said that they couldn’t “speculate” on whether the changes would impact their merger plans before they finished reviewing the rules. Investors, though, reacted as if the deal was already off the table.

Allergan’s stock was as as low as $230 on Tuesday. Pfizer’s stock price, meanwhile, rose nearly 3% on Tuesday, to $31.50. The drugmaker agreed in November to pay 11.3 of its own shares per Allergan share, which would translate into $356 per Allergan share. That means Allergan’s shares are about $126 lower than where they would trade if investors actually believed the deal would succeed—a gap so wade that it implies investors believe the deal is “95% dead,” according to Evercore ISI analyst Michael Craig.

Indeed, investors have been skeptical about the deal’s success ever since it was announced. And Allergan’s shares have been below Pfizer’s offer price for them for a while. But Allergan stock is now even cheaper than it was before rumors of a Pfizer deal first began to circulate last fall, which had caused the shares to rise. The selloff has also caused Allergan’s value to fall below what several Wall Street analysts (including at Cowen and RBC) think it’s worth as a standalone company—even if the Pfizer deal never happens.

Investors’ reaction stems from the perception that the Treasury may have just killed the merger, or at least made it a lot harder for Pfizer to reap the tax savings it sought, “potentially derailing” the deal, according to analysts at Jefferies.

At issue is how much Allergan, which is based in Ireland, will own of the combined company when the deal closes. In order for Pfizer to benefit from Allergan’s lower foreign tax rate through the deal, Allergan shareholders need to own at least 20% of the combined company, according to Treasury rules. While the companies thought they had safely cleared that threshold—with Allergan shareholders owning about 44% and Pfizer shareholders owning 56% of the new company—the Treasury’s new proposal threatens to throw that math out the window.

That’s because the Treasury’s new rules would exclude Allergan’s acquisitions of U.S. companies in the last three years—deals that not only made Allergan significantly bigger, but also allowed it to move to Ireland in the first place, through an acquisition of Warner Chilcott in 2013 (by Actavis, the company that bought Allergan in 2014).

(For a timeline of Allergan’s deals, see “From Actavis to Allergan: One pharma company’s wild dealmaking journey.”)

If the shares that Allergan acquired through those deals don’t count, it may not have enough total shares to meet the required threshold of ownership in Pfizer. For example, if you remove Actavis’ acquisition of Allergan, the Irish company’s stake in Pfizer drops to a third, according to Credit Suisse. But if you also exclude Actavis’ Warner Chilcott deal, the stake drops to just 19%—not enough to qualify Pfizer for Allergan’s lower foreign tax rate. “At this point we believe it is unlikely the deal will close,” Credit Suisse analysts led by Vamil Divan wrote in a research note.

About the Author
By Jen Wieczner
See full bioRight Arrow Button Icon

Latest in Finance

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025

Most Popular

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Fortune Secondary Logo
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • Future 50
  • World’s Most Admired Companies
  • See All Rankings
Sections
  • Finance
  • Fortune Crypto
  • Features
  • Leadership
  • Health
  • Commentary
  • Success
  • Retail
  • Mpw
  • Tech
  • Lifestyle
  • CEO Initiative
  • Asia
  • Politics
  • Conferences
  • Europe
  • Newsletters
  • Personal Finance
  • Environment
  • Magazine
  • Education
Customer Support
  • Frequently Asked Questions
  • Customer Service Portal
  • Privacy Policy
  • Terms Of Use
  • Single Issues For Purchase
  • International Print
Commercial Services
  • Advertising
  • Fortune Brand Studio
  • Fortune Analytics
  • Fortune Conferences
  • Business Development
About Us
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
Fortune Secondary Logo
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • Facebook icon
  • Twitter icon
  • LinkedIn icon
  • Instagram icon
  • Pinterest icon

Latest in Finance

basketball player celebrates on the court
EconomyNBA
NBA star’s partnership with a prediction market raises new questions for a troubled sports betting landscape
By Carlos GarciaMarch 1, 2026
58 minutes ago
iran
Middle EastMiddle East
3 U.S. service members killed and 5 seriously wounded in Iran operation, after Trump warned of casualties
By Ben Finley and The Associated PressMarch 1, 2026
2 hours ago
Middle EastMilitary
U.S. military gives Iran a taste of its own medicine with cheap copycat Shahed drones, while concern shifts to munitions supply in extended conflict
By Jason MaMarch 1, 2026
2 hours ago
Middle EastDubai
As Iran attacks Dubai, the tax-free haven for the global elite could see ‘catastrophic’ fallout — ‘this can also send shockwaves globally’
By Jason MaMarch 1, 2026
4 hours ago
woman looking stressed paying bills
FinanceGen Z
Gen Z can’t afford the American Dream—so they’ve traded homeownership for paying off debt. ‘Their debt feels heavier because it hits earlier’
By Sydney LakeMarch 1, 2026
5 hours ago
EnergyOil
Oil prices soar 10% as tanker traffic halts near the Strait of Hormuz amid Iran attacks while IRGC warns against passage. ‘Our ships will stay put’
By Jason MaMarch 1, 2026
5 hours ago

Most Popular

placeholder alt text
Economy
Your grandparents are the reason the U.S. isn't in a recession right now. That won't last forever
By Eleanor PringleMarch 1, 2026
12 hours ago
placeholder alt text
AI
The week the AI scare turned real and America realized maybe it isn't ready for what's coming
By Nick LichtenbergFebruary 28, 2026
1 day ago
placeholder alt text
Success
Japanese companies are paying older workers to sit by a window and do nothing—while Western CEOs demand super-AI productivity just to keep your job
By Orianna Rosa RoyleFebruary 27, 2026
2 days ago
placeholder alt text
Middle East
Iran is now on 'death ground' amid existential threat from U.S. attacks and could 'go big' in retaliation, former NATO commander warns
By Jason MaFebruary 28, 2026
1 day ago
placeholder alt text
Success
Walmart exec says U.S. workforces needs to take inspiration from China where ‘5 year-olds are learning DeepSeek’
By Preston ForeFebruary 27, 2026
3 days ago
placeholder alt text
Middle East
Dubai’s worst nightmare unfolds as Iran strikes Gulf neighbors
By Dana Khraiche, Fiona MacDonald and BloombergFebruary 28, 2026
1 day ago

© 2026 Fortune Media IP Limited. All Rights Reserved. Use of this site constitutes acceptance of our Terms of Use and Privacy Policy | CA Notice at Collection and Privacy Notice | Do Not Sell/Share My Personal Information
FORTUNE is a trademark of Fortune Media IP Limited, registered in the U.S. and other countries. FORTUNE may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.