ALLERGAN, the pharmaceutical company best known for producing Botox at its long-standing plant in Westport, has officially re-domiciled to the United States under new ownership by American pharma giant AbbVie.
The move reverses a major corporate decision from 2015, when Allergan shifted its headquarters from the US to Ireland following a merger with Actavis.
Changes to US tax policy under Donald Trump have made such schemes far less attractive to US companies.
AbbVie CEO Rob Michael said the 2017 U.S. tax reforms—cutting corporate tax rates and removing inversion incentives—were key to the company’s $60 billion acquisition of Allergan in 2020 and its recent re-registration in the US.
“Tax reform allowed us to acquire Allergan and re-domicile it into the US,” he told a public news conference.
While Allergan’s Westport plant remains operational and continues to manufacture Botox, the company’s corporate headquarters are now back in America.
In 2023, Allergan reported a turnover of $5 billion, with nearly ¾ of sales coming from the US.
The re-domiciling could just be the beginning: US pharma companies with major Irish operations—such as Eli Lilly and Johnson & Johnson—are increasingly investing back in the states amid political uncertainty.
AbbVie plans to invest over $10 billion in the US over the next decade, encouraged by Trump tax reforms and recent incentives in the “One Big Beautiful Bill.”
Trump has also threatened a 200% tariff if pharma companies don’t shift operations back to America.
Ireland is currently home to over 900 US multinationals, many of which are in pharma, tech, and finance.
These firms employ more than 200,000 people directly and indirectly support many more.
Allergan’s move raises worry about a potential exodus, especially if future US policies continue to punish offshore operations.
While Ireland still offers a favourable corporate tax rate and strong regulatory environment, the tide of US reshoring incentives could pose long-term risks to its role as a global hub for American business.