A tax inversion or corporate tax inversion is a form of
tax avoidance
Tax avoidance is the legal usage of the tax regime in a single territory to one's own advantage to reduce the amount of tax that is payable. A tax shelter is one type of tax avoidance, and tax havens are jurisdictions that facilitate reduced taxe ...
where a corporation restructures so that the current parent is replaced by a foreign parent, and the original parent company becomes a subsidiary of the foreign parent, thus moving its tax residence to the foreign country. Executives and operational headquarters can stay in the original country. The US definition requires that the original shareholders remain a majority control of the post-inverted company. In
US federal legislation a company which has been restructured in this manner is referred to as an inverted domestic corporation, and the term "corporate expatriate" is also used, for example in the
Homeland Security Act of 2002
The Homeland Security Act (HSA) of 2002 () was introduced in the aftermath of the September 11 attacks and subsequent mailings of anthrax spores. The HSA was cosponsored by 118 members of Congress. The act passed the U.S. Senate by a vote of ...
.
The majority of the less than 100 material tax inversions recorded since 1993 have been of US corporations (85 inversions), seeking to pay less to the US corporate tax system. The only other jurisdiction to experience a material outflow of tax inversions was the United Kingdom from 2007 to 2010 (22 inversions); however, UK inversions largely ceased after the reform of the UK corporate tax code from 2009 to 2012.
The first inversion was
McDermott International in 1983. Reforms by US Congress in 2004 halted "naked inversions", however, the size of individual "merger inversions" grew dramatically; in 2014 alone, they exceeded the cumulative value of all inversions since 1983. New US Treasury rules in 2014–16 blocked several major inversions (e.g. 2016 USD$160 billion
Pfizer
Pfizer Inc. ( ) is an American Multinational corporation, multinational Pharmaceutical industry, pharmaceutical and biotechnology corporation headquartered at The Spiral (New York City), The Spiral in Manhattan, New York City. Founded in 184 ...
–
Allergan plc inversion, and the 2015 USD$54 billion
AbbVie
AbbVie Inc. is an American pharmaceutical company headquartered in North Chicago, Illinois. It is ranked sixth on the list of largest biomedical companies by revenue. In 2023, the company's seat in Forbes Global 2000 was 74, and rank 89 on the ...
–
Shire plc
Shire plc was a UK-founded Jersey-registered specialty biopharmaceutical company. Originating in the United Kingdom with an operational base in the United States, its brands and products included Vyvanse, Lialda, and Adderall XR. Shire was acq ...
inversion), and the
Tax Cuts and Jobs Act of 2017
The Act to provide for reconciliation pursuant to titles II and V of the concurrent resolution on the budget for fiscal year 2018, , is a congressional revenue act of the United States originally introduced in Congress as the Tax Cuts and Jobs ...
(TCJA) further reduced the taxation incentives of inversions. , there have been no material US inversions post-2017, and notably, two large Irish-based tax inversion targets were acquired in non-tax inversion transactions, where the acquirer remained in their higher-tax jurisdiction:
Shire plc
Shire plc was a UK-founded Jersey-registered specialty biopharmaceutical company. Originating in the United Kingdom with an operational base in the United States, its brands and products included Vyvanse, Lialda, and Adderall XR. Shire was acq ...
by Japanese pharma
Takeda for US$63 billion (announced in 2018, closed in 2019), and
Allergan plc by U.S. pharma
AbbVie
AbbVie Inc. is an American pharmaceutical company headquartered in North Chicago, Illinois. It is ranked sixth on the list of largest biomedical companies by revenue. In 2023, the company's seat in Forbes Global 2000 was 74, and rank 89 on the ...
for US$64 billion (announced in 2019, expected to close in 2020); in addition,
Broadcom Inc. redomesticated to the United States.
the most popular destination in history for US corporate tax inversions is Ireland (with 22 inversions); Ireland was also the most popular destination for UK inversions. The largest completed corporate tax inversion in history was the US$48 billion merger of
Medtronic
Medtronic plc is an American-Irish medical device company. The company's legal and executive headquarters are in Republic of Ireland, Ireland, while its operational headquarters are in Minneapolis, Minneapolis, Minnesota. Medtronic rebased to I ...
with
Covidien plc in Ireland in 2015 (the vast majority of their merged revenues are still from the US). The largest aborted tax inversion was the US$160 billion merger of
Pfizer
Pfizer Inc. ( ) is an American Multinational corporation, multinational Pharmaceutical industry, pharmaceutical and biotechnology corporation headquartered at The Spiral (New York City), The Spiral in Manhattan, New York City. Founded in 184 ...
with Allergan plc in Ireland in 2016. The largest hybrid-
intellectual property
Intellectual property (IP) is a category of property that includes intangible creations of the human intellect. There are many types of intellectual property, and some countries recognize more than others. The best-known types are patents, co ...
(IP) tax inversion was the US$300 billion acquisition of
Apple Inc.
Apple Inc. is an American multinational corporation and technology company headquartered in Cupertino, California, in Silicon Valley. It is best known for its consumer electronics, software, and services. Founded in 1976 as Apple Comput ...
's IP by Apple Ireland in 2015.
Concept
While the legal steps taken to execute a tax inversion can be complex as the corporations need to avoid both regulatory and
Internal Revenue Service
The Internal Revenue Service (IRS) is the revenue service for the Federal government of the United States, United States federal government, which is responsible for collecting Taxation in the United States, U.S. federal taxes and administerin ...
(IRS) hurdles in re-locating their tax residence to a lower-tax jurisdiction, simplified examples are available; such as provided in August 2014, by Bloomberg journalist Matt Levine when reporting on the
Burger King
Burger King Corporation (BK, stylized in all caps) is an American multinational chain store, chain of hamburger fast food restaurants. Headquartered in Miami-Dade County, Florida, the company was founded in 1953 as Insta-Burger King, a Jacks ...
tax inversion to Canada. Before the 2017 TCJA, U.S. companies paid a corporate tax rate of 35% on all income they earned in both the U.S., and abroad, but they obtained a credit against their U.S. tax liability for the amount of any foreign tax paid. Given that the U.S. tax rate of 35% was one of the highest in the world , the corporate's maximum global tax liability should, therefore, have been 35%. This pre-TCJA U.S. tax system, was referred to as a "worldwide tax system", as opposed to the "territorial tax system" used by almost all other developed countries. Levine explained:
If we're incorporated in the U.S., we'll pay 35 percent taxes on our income in the U.S. and Canada and Mexico and Ireland and Bermuda and the Cayman Islands, but if we're incorporated in Canada ho operate a "territorial tax system" we'll pay 35 percent on our income in the U.S. but 15 percent in Canada and 30 percent in Mexico and 12.5 percent in Ireland and zero percent in Bermuda and zero percent in the Cayman Islands.
By changing its headquarters to another country with a territorial tax regime, the corporation typically pays taxes on its earnings in each of those countries at the specific rates of each country. In addition, the corporation executing the tax inversion may find additional tax avoidance strategies, called tools, that can ''shift'' untaxed profits from the higher-tax locations (e.g. the U.S.), to the new lower-tax country to which the corporation has now inverted.
History
The following are notable events in the history of US and non-US corporate tax inversions:
US experience
* 1983. The first officially recognized US corporate tax inversion was of
McDermott International from
Texas
Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...
to Panama.
Academics refer to it as a first-generation inversion.
* 1990. The relocation of
Flextronics from
California
California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...
to
Singapore
Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. The country's territory comprises one main island, 63 satellite islands and islets, and one outlying islet. It is about one degree ...
; however it is not considered as a full tax inversion.
* 1994. The second officially recognized US corporate tax inversion was of
Helen of Troy Limited
Helen of Troy Limited is an American publicly traded designer, developer and worldwide marketer of consumer brand-name housewares, health and home, and beauty products under owned and licensed brands. It is the parent corporation of OXO Interna ...
from
Texas
Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...
to
Bermuda
Bermuda is a British Overseas Territories, British Overseas Territory in the Atlantic Ocean, North Atlantic Ocean. The closest land outside the territory is in the American state of North Carolina, about to the west-northwest.
Bermuda is an ...
.
Academics refer to it as a second-generation inversion.
* 1994.
James R. Hines Jr. publishes the important
Hines–Rice paper, which shows that many US corporations had chosen to ''shift'' profits to tax havens, instead of using tax inversions.
* 1996–2004. The first major wave of US tax inversions mainly to Caribbean
tax haven
A tax haven is a term, often used pejoratively, to describe a place with very low tax rates for Domicile (law), non-domiciled investors, even if the official rates may be higher.
In some older definitions, a tax haven also offers Bank secrecy, ...
s such as
Bermuda
Bermuda is a British Overseas Territories, British Overseas Territory in the Atlantic Ocean, North Atlantic Ocean. The closest land outside the territory is in the American state of North Carolina, about to the west-northwest.
Bermuda is an ...
and
Cayman Islands
The Cayman Islands () is a self-governing British Overseas Territories, British Overseas Territory, and the largest by population. The territory comprises the three islands of Grand Cayman, Cayman Brac and Little Cayman, which are located so ...
; these inversions were mostly "naked inversions" where the corporate re-domiciled to a tax haven in which they had no existing business, and included:
Ingersoll-Rand
Ingersoll Rand Inc. is an American multinational company that provides flow creation and industrial products. The company was formed in February 2020 through the spinoff of the industrial segment of Ingersoll-Randplc (now known as Trane Technol ...
,
Accenture
Accenture plc is a global multinational professional services company originating in the United States and headquartered in Dublin, Ireland, that specializes in information technology (IT) services and management consulting. It was founded in 1 ...
,
Seagate,
Cooper, and
Tyco.
Academics refer to them as third-generation inversions.
* 2004. US Congress passes the
American Jobs Creation Act of 2004 (AJCA) with IRS Section 7874 that requires existing shareholders to own less than 80% of the new entity, and introduces a "substantial business activities" test in the new foreign location; AJCA ends "naked inversions" to Caribbean-type tax havens.
* 2009–2012. Several US inversions from the first wave to the Caribbean-type tax havens relocate to
OECD tax havens, such as Ireland (
Ingersoll-Rand
Ingersoll Rand Inc. is an American multinational company that provides flow creation and industrial products. The company was formed in February 2020 through the spinoff of the industrial segment of Ingersoll-Randplc (now known as Trane Technol ...
,
Accenture
Accenture plc is a global multinational professional services company originating in the United States and headquartered in Dublin, Ireland, that specializes in information technology (IT) services and management consulting. It was founded in 1 ...
,
Seagate,
Cooper, and
Tyco), and Switzerland (
Weatherford and
Noble
A noble is a member of the nobility.
Noble may also refer to:
Places Antarctica
* Noble Glacier, King George Island
* Noble Nunatak, Marie Byrd Land
* Noble Peak, Wiencke Island
* Noble Rocks, Graham Land
Australia
* Noble Island, Gr ...
), fearing a backlash from a new Democratic administration.
* 2012–2016. The second major wave of US tax inversions use mergers to meet the "substantial business activities" of IRS 7874; Ireland and the UK are main destinations and the size of these inversions are much larger than the first wave (see graphic), and included:
Medtronic
Medtronic plc is an American-Irish medical device company. The company's legal and executive headquarters are in Republic of Ireland, Ireland, while its operational headquarters are in Minneapolis, Minneapolis, Minnesota. Medtronic rebased to I ...
,
Liberty Global
Liberty Global Ltd. is a British-Dutch-American multinational telecommunications company domiciled in Bermuda, with headquarters in London, Amsterdam and Denver. Its respective legal names are Liberty Global Holdings Limited (UK), Liberty Glo ...
,
Eaton Corporation
Eaton Corporation plc is an American-Irish-domiciled multinational power management company, with a primary administrative center in Beachwood, Ohio. Eaton has more than 85,000 employees and sells products to customers in more than 175 countr ...
,
Johnson Controls, and
Perrigo.
Academics refer to them as fourth-generation inversions.
* 2012. The US Treasury issues T.D. 9592 increasing the "substantial business activities" threshold in the foreign destination from 10% to over 25%.
* 2014. The value of new proposed US tax inversions in 2014 alone (US$319 billion) exceeds the cumulative value of all previous US tax inversions in history.
* 2014. The US Treasury further tightens the regulations around the existing AJCA/TD 9592 thresholds;
AbbVie
AbbVie Inc. is an American pharmaceutical company headquartered in North Chicago, Illinois. It is ranked sixth on the list of largest biomedical companies by revenue. In 2023, the company's seat in Forbes Global 2000 was 74, and rank 89 on the ...
cancels a US$54 billion inversion to Ireland with
Shire plc
Shire plc was a UK-founded Jersey-registered specialty biopharmaceutical company. Originating in the United Kingdom with an operational base in the United States, its brands and products included Vyvanse, Lialda, and Adderall XR. Shire was acq ...
.
* 2015.
Medtronic
Medtronic plc is an American-Irish medical device company. The company's legal and executive headquarters are in Republic of Ireland, Ireland, while its operational headquarters are in Minneapolis, Minneapolis, Minnesota. Medtronic rebased to I ...
completes the largest tax inversion in history in a US$48 billion merger with
Covidien plc in Ireland.
* 2015.
Apple Inc.
Apple Inc. is an American multinational corporation and technology company headquartered in Cupertino, California, in Silicon Valley. It is best known for its consumer electronics, software, and services. Founded in 1976 as Apple Comput ...
completes the largest hybrid IP-inversion in history by moving US$300 billion of IP to Ireland (see
leprechaun economics
Leprechaun economics () was a term coined by economist Paul Krugman to describe the 26.3 per cent rise in Irish 2015 Gross domestic product, GDP, later revised to 34.4 per cent, in a 12 July 2016 publication by the Central Statistics Office ( ...
).
* 2015. Two previous US tax inversions to Ireland,
Actavis plc and
Allergan plc, execute a US$70 billion merger to prepare for a tax inversion with
Pfizer
Pfizer Inc. ( ) is an American Multinational corporation, multinational Pharmaceutical industry, pharmaceutical and biotechnology corporation headquartered at The Spiral (New York City), The Spiral in Manhattan, New York City. Founded in 184 ...
.
* 2016. The US Treasury tightens, and introduces new regulations around the existing AJCA/T.D. 9592 thresholds which blocks the US$160 billion merger of Pfizer with Allergan plc in Ireland.
* 2017. The US
Congressional Budget Office
The Congressional Budget Office (CBO) is a List of United States federal agencies, federal agency within the United States Congress, legislative branch of the United States government that provides budget and economic information to Congress.
I ...
forecasts a 2.5% (or US$12 billion) permanent reduction in annual US corporate tax revenues from inversions.
* 2017. The US Tax Cuts and Jobs Act reforms US tax code and introduces a lower 21% headline tax rate and moves to a hybrid–"territorial tax system".
* 2019.
AbbVie
AbbVie Inc. is an American pharmaceutical company headquartered in North Chicago, Illinois. It is ranked sixth on the list of largest biomedical companies by revenue. In 2023, the company's seat in Forbes Global 2000 was 74, and rank 89 on the ...
announced an agreement to acquire Allergan plc for $US63 billion; however the acquisition would not be structured as a tax inversion, and that the group would be domiciled in the U.S. for tax purposes.
AbbVie announced that post the 2017 TCJA, its effective tax rate was already lower than that of Irish-based Allergan plc at 9%, and that post the acquisition, it would rise to 13%.
UK experience
* 2007–2010. The United Kingdom loses a wave of tax inversions mainly to Ireland including:
Experian plc,
WPP plc
WPP plc is a British multinational communications, advertising, public relations, technology, and commerce holding company headquartered in London, England. It is the world's largest advertising company, as of 2023. WPP plc owns many companie ...
,
United Business Media plc,
Henderson Group plc,
Shire plc
Shire plc was a UK-founded Jersey-registered specialty biopharmaceutical company. Originating in the United Kingdom with an operational base in the United States, its brands and products included Vyvanse, Lialda, and Adderall XR. Shire was acq ...
, and
Charter
A charter is the grant of authority or rights, stating that the granter formally recognizes the prerogative of the recipient to exercise the rights specified. It is implicit that the granter retains superiority (or sovereignty), and that the ...
.
* 2009–2012. The United Kingdom reforms its corporate tax code introducing a lower 19% corporate tax rate and moves to a full "territorial tax system".
* 2013.
Liberty Global
Liberty Global Ltd. is a British-Dutch-American multinational telecommunications company domiciled in Bermuda, with headquarters in London, Amsterdam and Denver. Its respective legal names are Liberty Global Holdings Limited (UK), Liberty Glo ...
completes the second largest US tax inversion in history in a US$24 billion merger with
Virgin Media
Virgin Media Limited is a British telecommunications company which provides telephone, television and internet services in the United Kingdom. Its headquarters are at Green Park in Reading, England. It is owned by Virgin Media O2, a 50:50 ...
in the UK.
* 2015. The UK
HMRC
His Majesty's Revenue and Customs (commonly HM Revenue and Customs, or HMRC, and formerly Her Majesty's Revenue and Customs) is a Departments of the United Kingdom Government, department of the UK government responsible for the tax collectio ...
reports many UK inversions to Ireland returned (e.g.
WPP plc
WPP plc is a British multinational communications, advertising, public relations, technology, and commerce holding company headquartered in London, England. It is the world's largest advertising company, as of 2023. WPP plc owns many companie ...
,
United Business Media plc,
Henderson Group plc); and that the UK was a major destination for US inversions.
* 2016. The UK becomes the third most popular destination in history for US tax inversions with 11 inversions (Ireland is top with 21 inversions).
Other experience
* 2014. Irish
International Financial Services Centre International Financial Services Centre may refer to any of the following places:
* International Financial Services Centre, Dublin
The International Financial Services Centre (IFSC; ) is an area of central Dublin and part of the Central busi ...
tax-law firms sometimes list
Pentair
Pentair plc (PNR) is an American water treatment company incorporated in Ireland with tax residency in UK, with its main U.S. office in Golden Valley, Minnesota, Golden Valley, Minnesota. Pentair was founded in the US, with 65% of company's reve ...
in their brochures as a Swiss tax inversion to Ireland; however Pentair was really a 2012 US tax inversion to Switzerland, who then used Ireland as a base for two years, before moving to the UK in 2016.
* 2018. The Japanese
Takeda Pharmaceutical Company
The is a Japanese multinational pharmaceutical company. It is the third largest pharmaceutical company in Asia, behind Sinopharm and Shanghai Pharmaceuticals, and one of the top 20 largest pharmaceutical companies in the world by revenue (t ...
announced that it was merging with Irish-based
Shire plc
Shire plc was a UK-founded Jersey-registered specialty biopharmaceutical company. Originating in the United Kingdom with an operational base in the United States, its brands and products included Vyvanse, Lialda, and Adderall XR. Shire was acq ...
(a previous UK inversion to Ireland in 2008); however, after some initial confusion, Takeda clarified that it was not executing an inversion to Ireland and that its legal headquarters would remain in Japan.
Drivers
Reduced taxes

While corporates who execute inversions downplay taxation in their rationale for the transaction, and instead emphasise strategic rationale,
research is unanimous that tax was the driver for most US tax inversions from 1983 to 2016.
Types of tax saving
US research on US tax inversions breaks down the tax savings into three areas:

* ''Tax on US income''. Before the 2017 TCJA, the US corporate tax rate was one of the highest rates in the developed world at 35%.
The development of that could ''shift'' or ''earnings strip'' US-sourced profits to other jurisdictions without incurring US taxes, created an incentive for US corporates to execute tax inversions to lower tax jurisdictions.
The "first wave" of US inversions from 1996 to 2004 focused on debt-based tools, however, the significantly larger "second wave" of US inversions from 2012 to 2016 also made use of IP-based BEPS tools.
* ''Tax on non-US income''. Before the 2017 TCJA, the US corporate tax code applied the 35% rate of taxation to all worldwide corporate profits.
The US was one of only eight jurisdictions using a "worldwide tax system".
All other jurisdictions used a "territorial tax system" where very low rates of taxation are applied to foreign-sourced profits (e.g. in Germany was at 5%).
US tax academics noted this was the reason why non-US corporations made limited use of tax havens;
in contrast, US corporations have been shown to be
the largest global users of tax havens.
* ''Tax on offshore reserves''. Tax academics have shown that the dominance of US corporations in using tax havens was driven by strategies to shield non-US income from US taxation.
BEPS tools such as the "
Double Irish
The Double Irish arrangement was a base erosion and profit shifting (BEPS) corporate tax avoidance tool used mainly by United States multinationals since the late 1980s to avoid corporate taxation on non-U.S. profits. (The US was one of a sma ...
",
enabled US corporations to build up untaxed offshore cash reserves estimated at US$1–2 trillion in 2017.
Ensuring that such reserves would be protected from any initiatives by Congress to subject them to US taxes required an inversion to another jurisdiction.
Medtronic's US$20 billion in untaxed offshore reserves was noted as a driver for their 2015 inversion.
In 2015, the UK
HMRC
His Majesty's Revenue and Customs (commonly HM Revenue and Customs, or HMRC, and formerly Her Majesty's Revenue and Customs) is a Departments of the United Kingdom Government, department of the UK government responsible for the tax collectio ...
identified high corporate taxes and a "worldwide tax system" for the wave of UK tax inversions to Ireland in 2007–2010.
Evidence of tax savings
In September 2017, the US Congressional Budget Office analyzed the post-tax outcomes of US corporate tax inversions from 1994 to 2014, and found the following:
* After year one, the aggregate effective rate of worldwide taxation of the inverted company fell from a 29% rate to an 18% rate; and
* By year three, the aggregate worldwide tax expense was 34% lower, while the US tax expense was 64% lower.
A 2014 report by the ''
Financial Times
The ''Financial Times'' (''FT'') is a British daily newspaper printed in broadsheet and also published digitally that focuses on business and economic Current affairs (news format), current affairs. Based in London, the paper is owned by a Jap ...
'' on US pharmaceutical tax inversions during 2012–2014, showed their aggregate worldwide tax rates dropped from 26 to 28% to 16–21%.
A similar 2014 study by ''
Forbes Magazine
''Forbes'' () is an American business magazine founded by B. C. Forbes in 1917. It has been owned by the Hong Kong–based investment group Integrated Whale Media Investments since 2014. Its chairman and editor-in-chief is Steve Forbes. The c ...
'' using the projected post-inversion tax rates from the inverting corporates also confirmed the same movement in tax rates.
Shareholder impact
A number of studies have shown that the after-tax returns to original company shareholders post-inversion are more mixed, and often poor:
* A 2014 report by
Reuters
Reuters ( ) is a news agency owned by Thomson Reuters. It employs around 2,500 journalists and 600 photojournalists in about 200 locations worldwide writing in 16 languages. Reuters is one of the largest news agencies in the world.
The agency ...
on 52 completed US tax inversions since 1983 showed that 19 outperformed the S&P500, another 19 underperformed the S&P500, another 10 were bought by rivals, another 3 went bankrupt and the final one returned to the US. Reuters concluded that: "But the analysis makes one thing clear: inversions, on their own, despite largely providing the tax savings that companies seek, are no guarantee of superior returns for investors".
* A 2017 study published in the ''
Journal of Financial Economics
The ''Journal of Financial Economics'' is a peer-reviewed academic journal published by Elsevier, covering the field of finance. It is considered to be one of the premier finance journals. According to the ''Journal Citation Reports'', the journa ...
'', found that while inversions lowered the corporate tax and increased the economic value of the corporate, the after-tax benefits to shareholders were distributed disproportionately. CEOs and short-term shareholders, foreign shareholders, and tax-exempt shareholders benefitted disproportionately from inversions. However, long-term domestic shareholders did not benefit from inversions, since the US tax code requires taxable shareholders to recognize their capital gains at the time of the inversion.
* A 2019 study published in the ''
International Review of Financial Analysis'', found in the short-term, shares of inverting corporates increased in value. In the medium to longer-term, however, they found that the share price tended to decline. The driver was shown to be partly agency costs, and a distinction was drawn between the material gains of the CEO from the inversion and the losses of long-term shareholders. There were concerns on the acquisition premiums paid in inversion mergers, and that inversions tended to be favoured by corporates with poor growth outlooks.
Types
Definition

In 2017, the US
Congressional Budget Office
The Congressional Budget Office (CBO) is a List of United States federal agencies, federal agency within the United States Congress, legislative branch of the United States government that provides budget and economic information to Congress.
I ...
(CBO) stated that it only considered a transaction to be a tax inversion under the following conditions:

In all definitions, the executive management (e.g. CEO, CFO), and the substantive offices and assets of the company, can remain in the US.
For example, the executives of Medtronic, who executed the largest tax inversion in history by legally moving Medtronic to Ireland in 2015, remained in their main operational headquarters of
Fridley, Minnesota in the US. All of Medtronic's substantive business and management operations still reside in the US.
Sometimes, the 2015 US$70 billion merger of
Allergan plc and
Activis plc, both previous US tax inversions to Ireland, are listed as a tax inversion (and the largest executed inversion in history). However, as both companies were legally Irish companies, their merger was not considered a tax inversion.
Major classes
In 2019, in the "anatomy of an inversion" the US
Congressional Research Service
The Congressional Research Service (CRS) is a public policy research institute of the United States Congress. Operating within the Library of Congress, it works primarily and directly for members of Congress and their committees and staff on a ...
(CRS) classified US tax inversion into three broad types:
* ''Substantial business presence''. A US corporation creates a new foreign subsidiary, and exchanges each other's equity in proportion to their valuations so that after the exchange, the new entity is a foreign corporation with a US subsidiary. There is no "change of control". This is also called a "naked tax inversion", a "shell inversion", a "self-help inversion",
a "pure inversion", or "redomiciling".
Since the 2004 ACJA, and the 2012–16 Treasury rules, only US corporations with an existing "substantial business presence" in the foreign location that constitutes more than 25% of the post-inversion corporation (called the "expanded affiliate group" (EAG) in the legalisation) can execute a "self-inversion".
This stopped US corporations inverting to smaller tax havens.
* ''US corporation acquired by a larger foreign corporation''. A US corporation merges with a larger foreign corporation. The US shareholders, therefore, own a minority of the merged group and "effective control" moves outside of the US to the shareholders of the foreign corporation.
The CBO does not recognize these transactions as being tax inversions (including where the acquiring corporation is a
private equity
Private equity (PE) is stock in a private company that does not offer stock to the general public; instead it is offered to specialized investment funds and limited partnerships that take an active role in the management and structuring of the co ...
fund, or the transaction is from a bankruptcy).
* ''A smaller foreign corporation acquired by a larger US corporation''. A US corporation merges with a smaller foreign corporation who becomes the new legal parent of the group. The existing US shareholders still own a majority merged group this thus maintain "effective control", however, it is now a ''foreign company'' under the US tax code.
The CBO considers these types of transactions as tax inversions (a "merger tax inversion").
Since 2004 ACJA and 2012–16 Treasury rules, only mergers where the existing US shareholders own less than 80% of the EAG are recognized as foreign by the IRS (and mergers where the foreign-headquartered EAG is still over 80% owned by the original US corporate shareholders, is considered by the IRS to be a US corporation for taxation purposes).
Hybrid inversions
In 1994, US tax academic
James R. Hines Jr. published the important
Hines–Rice paper, which showed that many US corporations had chosen to ''shift'' profits to tax havens, instead of outright moving to the tax haven by executing a tax inversion.
Hines, and later again with US tax academic
Dhammika Dharmapala
Dhammika Dharmapala (born 1969/1970) is an economist who is the Paul H. and Theo Leffman Professor of Law at the University of Chicago Law School. He is known for his research into corporate tax avoidance, corporate use of tax havens, and the cor ...
, would show that
base erosion and profit shifting (BEPS), was an even greater loss of corporate tax revenue to the US exchequer, than full tax inversions.
In 2018, academics identified a new class of tax inversion as details of Apple's Q1 2015 leprechaun economics transaction in Ireland emerged.
While Apple's tax residence remained in the US,
Apple moved the legal tax residence of a large part of its business to Ireland in a US$300 billion quasi-tax inversion of its intellectual property (IP).
[
The use of IP-based BEPS tools (e.g. Apple and Google's ]Double Irish
The Double Irish arrangement was a base erosion and profit shifting (BEPS) corporate tax avoidance tool used mainly by United States multinationals since the late 1980s to avoid corporate taxation on non-U.S. profits. (The US was one of a sma ...
and Microsoft's Single Malt), has been attributed as the driver for the reduction in the ''marginal'' aggregate effective US corporate tax rate, falling from circa 30% in 2000, to circa 20% by 2016 (see graphic). For example, the CAIA BEPS tool Apple used in 2015 would give Apple an " effective tax rate" of under 2.5% on the worldwide profits Apple generated on this IP that was ''shifted'' to Ireland.
However, these IP assets had normally been housed in small Caribbean tax haven-type locations; Apple has been reported as using Bermuda and Jersey to house its IP. Such locations could not meet the 25% "substantive business test" of regulation T.D. 9592 for an inversion. However, Apple's 2015 BEPS transaction to Ireland was the first time a US corporation moved a substantial amount of IP to a full OECD jurisdiction where it already had a "substantive business operations".
In July 2018, Seamus Coffey, Chairperson of the Irish Fiscal Advisory Council
Irish Fiscal Advisory Council (Fiscal Council; ) is a non-departmental statutory body providing independent assessments and analysis of the Irish Government's fiscal stance, its economic and budgetary forecasts, and its compliance with fiscal rul ...
and author of the Irish State's 2016 review of the ''Irish Corporate Tax Code'', posted that Ireland could see a "boom" in the ''onshoring'' of U.S. IP, via the CAIA BEPS tool, between now and 2020, when the Double Irish is fully closed. In February 2019, Brad Setser from the Council on Foreign Relations
The Council on Foreign Relations (CFR) is an American think tank focused on Foreign policy of the United States, U.S. foreign policy and international relations. Founded in 1921, it is an independent and nonpartisan 501(c)(3) nonprofit organi ...
, wrote a ''New York Times
''The New York Times'' (''NYT'') is an American daily newspaper based in New York City. ''The New York Times'' covers domestic, national, and international news, and publishes opinion pieces, investigative reports, and reviews. As one of ...
'' article highlighting issues with TCJA in terms of combatting power of BEPS tools.
Industries
In 2017, the Congressional Budget Office reported that of the 60 US tax inversions from 1983 to 2015 which the CBO officially recognize, over 40% came from three industries: Pharmaceutical preparations (9), Fire, marine, and casualty insurance (7), and Oil & Gas Well Drilling and Servicing (7).
The US Oil & Gas Well Drilling and Servicing and US Casualty Insurance inversions are mostly associated with the first wave of US tax inversions before 2004; the very first US tax inversion, McDermott International in 1983, was from the Oil & Gas Well Drilling and Servicing industry. These US companies that inverted in these two industries shared the common attributes of having mostly international client bases, and of having assets that were easily "portable" outside of the US. The assets of the Oil & Gas corporate tax inversions were already mostly held in securitization
Securitization is the financial practice of pooling various types of contractual debt such as residential mortgages, commercial mortgages, auto loans, or credit card debt obligations (or other non-debt assets which generate receivables) and sellin ...
vehicles often legally located in offshore financial centres. Similarly, the assets of the Casualty Insurance corporate tax inversions were also mainly global reinsurance contracts that were also legally located in offshore financial centres.
The US Life Sciences industry (Pharmaceutical and Medical Devices) became a significant part of the second wave of US tax inversions from 2012 to 2016. It also involved some of the largest and most public executed US tax inversions (e.g. Medtronic
Medtronic plc is an American-Irish medical device company. The company's legal and executive headquarters are in Republic of Ireland, Ireland, while its operational headquarters are in Minneapolis, Minneapolis, Minnesota. Medtronic rebased to I ...
(2015) and Perrigo (2013)), as well as the aborted 2016 inversion of Pfizer
Pfizer Inc. ( ) is an American Multinational corporation, multinational Pharmaceutical industry, pharmaceutical and biotechnology corporation headquartered at The Spiral (New York City), The Spiral in Manhattan, New York City. Founded in 184 ...
and Allergan
Allergan plc is an American, Irish-domiciled pharmaceutical company that acquires, develops, manufactures and markets brand name drugs and medical devices in the areas of medical aesthetics, eye care, central nervous system, and gastroenterology. ...
, which would have been largest inversion in history at US$160 billion.
In July 2015, ''The Wall Street Journal
''The Wall Street Journal'' (''WSJ''), also referred to simply as the ''Journal,'' is an American newspaper based in New York City. The newspaper provides extensive coverage of news, especially business and finance. It operates on a subscriptio ...
'' reported that the circa 4% " effective tax rate" being paid by US pharmaceuticals who inverted to Ireland made them highly acquisitive of other US firms (i.e. they could afford to pay more to acquire US competitors and redomicile them to Ireland). The WSJ listed the extensive post-inversion acquisitions of Activis/Allergan, Endo, Mallinckrodt and Horizon.
In August 2016, after the US Treasury blocked Pfizer's US$160 billion tax inversion to Ireland with Allergan, Bloomberg stated that "Big Pharma Murdered Tax Inversions".
Earnings stripping
An important concept in inversions are the tools required to ''shift'' untaxed profits from the corporate's existing operating jurisdictions to the new destination. This is known as ''earnings stripping''. Without these tools, a tax inversion might not deliver the expected tax savings, as the profits might arrive at the new destination having incurred full taxes in the jurisdictions in which they were sourced.
For example, when Medtronic inverted to Ireland in 2015, over 60% of the merged group's revenue still came from the US healthcare system. Similarly, over 80% of Allergan's revenues comes from the US healthcare system post its Irish inversion. Medtronic and Allergan, therefore, could only avail of Ireland's lower effective tax rates if they could ''shift'' US-sourced profits to Ireland without incurring full US corporate taxes. Studies have shown that the ''earnings stripping'' of US-sourced earnings is a critical component of reducing the aggregate effective tax rate post the inversion (per ).
The two main types of tools used in tax inversions are:
* ''Debt-based tools''. This is where the foreign parent of the newly inverted company raises debt to acquire the original US company. This debt is then "moved down" into the US subsidiary and the US profits are thus ''shifted'' untaxed to the foreign patent via interest payments on this debt. Early US tax inversions involved highly leveraged structures with real external debt.
* ''IP-based BEPS tools''. This is where the IP of the newly inverted group is moved to the lower-tax jurisdiction of the parent, who charges it out to the higher-tax jurisdictions in which the group operates (including its original US jurisdiction). This can only be achieved where the IP is already housed in an offshore location (e.g. Bermuda), so that its movement does not itself incur US tax charges.
created in the 2017 TCJA, directly targeted debt-based tools via the new BEAT tax, and introduce a competing US IP-based BEPS tool called the FDII tax.
Costs
There have been several estimates of the ''aggregate'' cost of US tax inversions to the US exchequer (also called the erosion of the US tax base). However, there is a significant variation in these ''aggregate'' estimates of tax erosion over the years due to two specific factors:
* ''Variation in US inversions''. Firstly, there has been material variation in the financial scale of inversions since 1983. In 2014, a Joint Committee on Taxation (JCT), estimated that stopping inversions would prevent US$19.5 billion in lost taxes over the next decade (2015–2024), or US$1.95 billion annually on average. At the time, this figure was just 0.4% of the estimated total US corporate taxation revenues for the next decade, of US$4.5 trillion (2015–2024). However, just three years later, the scale of US tax inversions had increased dramatically, leading the CBO to re-forecast in 2017 that by 2027, annual US taxes would be circa 2.5% (or US$12 billion) lower due to tax inversions.
* ''Effect of hybrid inversions''. Secondly, estimates can vary dramatically depending on whether the effect of hybrid inversions is included. The CBO (and other US State estimates above) ignore hybrid inversions. In 2016, tax academic Kimberly Clausing estimated that the loss to the US exchequer from all classes of inversions, using the broadest types of hybrid inversions (and all base erosion and profit shifting earnings stripping activity), by US corporations was between US$77 to US$111 billion in 2012 (having been zero 20 years ago).
Destinations
US inversions
The US Congressional Budget Office and the Congressional Research Service have cataloged 85 US tax inversions since 1983 to 2017 (the CBO does not recognize all of them as official tax inversions). Bloomberg
Bloomberg may refer to:
People
* Daniel J. Bloomberg (1905–1984), audio engineer
* Georgina Bloomberg (born 1983), professional equestrian
* Michael Bloomberg (born 1942), American businessman and founder of Bloomberg L.P.; politician a ...
used this data to identify the most attractive destinations for US inversions titled ''Tracking the Tax Runaways'' which won the 2015 Pulitzer Prize for Explanatory Reporting, and was updated to 2018.
The first wave of US tax inversions from 1996 to 2004 was mainly to Caribbean tax havens
A tax haven is a term, often used pejoratively, to describe a place with very low tax rates for non-domiciled investors, even if the official rates may be higher.
In some older definitions, a tax haven also offers financial secrecy. However, ...
such as Bermuda and the Cayman Islands. These were mostly "naked inversions" where the company had little or no previous "substantial business activities" in the location. They also used debt-based ''earnings stripping'' tools to shift US profits to the new destination. The 2004 ACJA ended these types of "naked inversions" with IRS Section 7874.
A significantly larger second wave of US tax inversions from 2012 to 2016 was mainly to the OECD tax havens of Ireland, and after their 2009 reforms, to the United Kingdom. These inversions involved mergers with real companies that met the "substantial business activities" test of IRS Section 7874. These destinations also had advanced IP-based BEPS tools (e.g. the Irish CAIA tool, the Double Irish tool, the UK Patent box tool) that could deliver an " effective tax rate" closer to zero on profits ''shifted'' to the destination.
The destinations for the 85 US corporate tax inversions since 1983 are as follows:
UK inversions
A 2012 article in ''Tax Notes'' listed the 22 tax inversions of UK companies to other destinations from 2006 to 2010, until UK tax reform ceased further material inversions.
While the full list is not available, the US Tax Foundation
The Tax Foundation is an international research think tank based in Washington, D.C. that collects data and publishes research studies on Taxation in the United States, U.S. tax policies at both the federal and state levels. Its stated mission ...
listed the nine most important UK inversions of which six went to Ireland ( Experian plc, WPP plc
WPP plc is a British multinational communications, advertising, public relations, technology, and commerce holding company headquartered in London, England. It is the world's largest advertising company, as of 2023. WPP plc owns many companie ...
, United Business Media plc, Henderson Group plc, Shire plc
Shire plc was a UK-founded Jersey-registered specialty biopharmaceutical company. Originating in the United Kingdom with an operational base in the United States, its brands and products included Vyvanse, Lialda, and Adderall XR. Shire was acq ...
, and Charter International), and one each went to Switzerland (Informa
Informa plc is a British publishing, business intelligence, and exhibitions group based in London, England. It is listed on the London Stock Exchange and is a constituent of the FTSE 100 Index.
It has offices in 30 countries and around 12,000 ...
), Luxembourg ( Regus), and the Netherlands ( Brit Insurance).
Other jurisdictions
Few other jurisdictions outside of the US and the UK have experienced a material outflow of corporate tax inversions to other destinations.
Countermeasures
United States
There have been three phases of initiatives that the US Government have taken to counter US corporate tax inversions:
* ''2004 American Jobs Creation Act
The American Jobs Creation Act of 2004 () was a federal tax act that repealed the export tax incentive (ETI), which had been declared illegal by the World Trade Organization several times and sparked retaliatory tariffs by the European Union. I ...
(ACJA)'':
:In 2002, the US Treasury reported to Congress that there had been a "marked increase in the frequency, size, and visibility" of "naked inversions". The Treasury cited three concerns: the erosion of the US tax base, a cost advantage for foreign-controlled firms, and a reduction in perceived fairness of the tax system. In response, Congress passed the AJCA, which added Section 7876 to the US tax-code that effectively ended "naked inversions" to Caribbean-type tax havens where the US corporation had no previous business presence in the location. The main provisions were:
:* US inversions where the existing US shareholders owned more than 80% of the post-inversion group, or Expanded Affiliate Group (EAG), would not be recognized.
:* Where the existing US shareholders owned between 60% but less than 80% of the EAG, the inversion would be recognized as a foreign company but with restricted tax benefits.
:* Section 7876 included a "safe harbour" from its provisions where the EAG had an existing "substantive business presence" in the foreign country but left it to the Treasury to define what this meant.
:* Shortly afterwards, the Treasury stated that to meet the "substantive business presence" the EAG had to have had over 10% of its employees, and assets, and income in the foreign location.
* ''2012–2016 US Treasury Regulations'':
** In 2012, the Treasury issued regulation T.D. 9592 that increased the threshold for the "substantive business presence" safe harbour exemption from Section 7876, from 10% to 25%.
** In 2014, the Treasury issued tax notice 2014–52 that blocked various legal structuring techniques to circumvent the earlier ACJA and TD 9592 regulations; AbbVie and Chiquita cancel inversions.
** In 2016, the Treasury issued a series of rulings to clarify past rulings, and introduce new provisions that blocked additional legal structuring techniques to circumvent the ACJA.
** In 2016, two days after the final Treasury ruling in 2016, Pfizer announced that it was aborting its planned US$160 billion tax inversion to Ireland via a merger with Allergan plc.
* ''2017 Tax Cuts and Jobs Act
The Act to provide for reconciliation pursuant to titles II and V of the concurrent resolution on the budget for fiscal year 2018, , is a congressional revenue act of the United States originally introduced in Congress as the Tax Cuts and Jobs ...
(TCJA)'':
: While the 2004 ACJA and the 2012–2016 Treasury Regulations sought to block US corporate tax inversions, the TCJA attempted to remove the taxation incentives by reforming elements of the US tax code. Such a reform had been completed by the UK in 2009–2012 (see below). The main provisions were:
:* Reduction in the headline US corporate tax rate from 35% to 21%.
:* Transformation of the US corporate tax code from a "worldwide tax system" to a hybrid-"territorial tax system".
:* Specific anti-US earnings stripping provisions such as the BEAT tax.
:* New US IP-based BEPS tools such as the 13.125% FDII tax rate.
In Q1 2018, U.S. multinationals like Pfizer announced in Q1 2018, a post-TCJA global tax rate for 2019 of circa 17%, which is close to the circa 15–16% 2019 tax rate guided by previous U.S. corporate tax inversions to Ireland including: Eaton, Allergan, and Medtronic. In March 2018, the Head of Life Sciences in Goldman Sachs made the following comment:
Federal procurement regulations require corporations bidding for government contracts to affirm that they are not inverted domestic corporations and require contractors who do become inverted domestic corporations to notify their Contracting Officer within five business day
A business day normally means any day except a legal holiday. It may also mean a business day of operation, any of the days an organization operates. It depends on the local workweek which is dictated by local customs, religions, and business ...
s of the change of their status.
In a report to Congress in March 2019, the Congressional Research Service noted that "there are also indications that most tax motivated inversions had already been discouraged by the 2016 regulations" and that since the 2017 TCJA that "Some firms appear to be considering reversing their headquarters r past inversiondecision". In June 2019, U.S.-based AbbVie
AbbVie Inc. is an American pharmaceutical company headquartered in North Chicago, Illinois. It is ranked sixth on the list of largest biomedical companies by revenue. In 2023, the company's seat in Forbes Global 2000 was 74, and rank 89 on the ...
announced an agreement to acquire Irish-based Allergan plc for US$63 billion; however the acquisition would not be structured as a tax inversion, and that the Group would be domiciled in the U.S. for tax purposes. AbbVie announced that post the 2017 TCJA, its effective tax rate was already lower than that of Irish-based Allergan plc at 9%, and that post the acquisition, it would rise to 13%. In 2014 the U.S. Treasury effectively blocked AbbVie's attempt to execute a tax inversion with Irish-based Shire plc.
United Kingdom
After losing 22 tax inversions from 2007 to 2010, mostly to Ireland, the UK moved to reform its corporate tax code from 2009 to 2012, executing the following:
* Reduction in the headline UK corporate tax rate from 28% to 20% (and eventually to 19%).
* Transformation of the UK corporate tax code from a "worldwide tax system" to a "territorial tax system".
* Creation of new IP-based BEPS tools including a low-tax Patent box.
In 2014, ''The Wall Street Journal
''The Wall Street Journal'' (''WSJ''), also referred to simply as the ''Journal,'' is an American newspaper based in New York City. The newspaper provides extensive coverage of news, especially business and finance. It operates on a subscriptio ...
'' reported that "In U.S. tax inversion Deals, U.K. is now a winner". In a 2015 presentation, the UK HMRC
His Majesty's Revenue and Customs (commonly HM Revenue and Customs, or HMRC, and formerly Her Majesty's Revenue and Customs) is a Departments of the United Kingdom Government, department of the UK government responsible for the tax collectio ...
showed that many of the outstanding UK inversions from 2007 to 2010 period had returned to the UK as a result of the tax reforms (most of the rest had entered into subsequent transactions and could not return, including Shire
Shire () is a traditional term for an administrative division of land in Great Britain and some other English-speaking countries. It is generally synonymous with county (such as Cheshire and Worcestershire). British counties are among the oldes ...
).
Notable inversions
US inversions
Executed
Of the 85 tax inversions executed by US corporates to other jurisdictions, the following are notable:
* 1982 McDermott International to Panama, first-ever tax inversion, and first ever "naked inversion"; only ever US tax inversion to Panama.
* 1994 Helen of Troy
Helen (), also known as Helen of Troy, or Helen of Sparta, and in Latin as Helena, was a figure in Greek mythology said to have been the most beautiful woman in the world. She was believed to have been the daughter of Zeus and Leda (mythology), ...
to Bermuda, second-ever tax inversion and also a "naked inversion".
* 1997 Tyco International
Tyco International was a security systems company incorporated in the Republic of Ireland, with operational headquarters in Princeton, New Jersey, United States (Tyco International (US) Inc.). Tyco International was composed of two major busin ...
to Bermuda; Tyco would later spin-off Covidien
Covidien plc was an Irish-headquartered global health care products company and manufacturer of medical devices and supplies. Covidien became an independent publicly traded company after being spun off from Tyco International in 2007. It was pu ...
who would execute the largest inversion in history with Medtronic in 2015; Tyco itself would merge with Johnson Controls in 2016 in the 3rd-largest inversion in history.
* 1998 Fruit of the Loom
Fruit of the Loom is an American company that manufactures clothing, particularly casual wear and undergarment, underwear. The company's world headquarters are located in Bowling Green, Kentucky. Since 2002, it has been a wholly owned subsidiary ...
to the Cayman Islands; entered into bankruptcy 3 years later and was then bought by Berkshire Hathaway
Berkshire Hathaway Inc. () is an American multinational conglomerate holding company headquartered in Omaha, Nebraska. Originally a textile manufacturer, the company transitioned into a conglomerate starting in 1965 under the management of c ...
.
* 1999 Transocean
Transocean Ltd. is an American drilling company. It is the world's largest offshore drilling contractor based on revenue and is based in Steinhausen, Switzerland. The company has offices in 20 countries, including Canada, the United States, ...
to the Cayman Islands.
* 2001 Ingersoll Rand to Bermuda; would "self-invert" to Ireland in 2009.
* 2001 Accenture
Accenture plc is a global multinational professional services company originating in the United States and headquartered in Dublin, Ireland, that specializes in information technology (IT) services and management consulting. It was founded in 1 ...
to Bermuda, would later "self-invert" to Ireland in 2009 to become Ireland's first tax inversion and first Irish CAIA BEPS tool user.
* 2003 Capri Holdings / Michael Kors
Michael David Kors (born Karl Anderson Jr. August 9, 1959) is an American fashion designer. He is the chief creative officer of his brand, Michael Kors, which sells men's and women's ready-to-wear, accessories, watches, jewelry, footwear, and f ...
to the British Virgin Islands; only ever US inversion to the BVI, later self-inverted to the UK.
* 2009 Valaris to the United Kingdom, first US inversion to the UK.
* 2012 Eaton Corporation
Eaton Corporation plc is an American-Irish-domiciled multinational power management company, with a primary administrative center in Beachwood, Ohio. Eaton has more than 85,000 employees and sells products to customers in more than 175 countr ...
to Ireland with a $US12 billion merger with Cooper Industries
Cooper Industries was an American worldwide electrical products manufacturer headquartered in Houston, Texas. Founded in 1833, the company had seven operating divisions including Bussmann electrical and electronic fuses; Crouse-Hinds Company, Cro ...
, 4th-largest inversion in history.
* 2013 Actavis
Actavis Generics (formerly known as Watson Pharmaceuticals and Actavis plc, prior to the acquisition of Irish-based Allergan, Inc.) is a global pharmaceutical company focused on acquiring, developing, manufacturing and marketing branded pharmaceut ...
to Ireland with a US$5 billion merger with Warner Chilcott, and would later execute a US$70 billion merger with Allergan
Allergan plc is an American, Irish-domiciled pharmaceutical company that acquires, develops, manufactures and markets brand name drugs and medical devices in the areas of medical aesthetics, eye care, central nervous system, and gastroenterology. ...
in Ireland in 2015.
* 2013 Liberty Global
Liberty Global Ltd. is a British-Dutch-American multinational telecommunications company domiciled in Bermuda, with headquarters in London, Amsterdam and Denver. Its respective legal names are Liberty Global Holdings Limited (UK), Liberty Glo ...
to the United Kingdom with a US$23 billion merger with Virgin Media
Virgin Media Limited is a British telecommunications company which provides telephone, television and internet services in the United Kingdom. Its headquarters are at Green Park in Reading, England. It is owned by Virgin Media O2, a 50:50 ...
, 2nd-largest inversion in history.
* 2013 Perrigo to Ireland with a US$9 billion merger with Elan Corporation, 6th-largest inversion in history.
* 2014 Burger King
Burger King Corporation (BK, stylized in all caps) is an American multinational chain store, chain of hamburger fast food restaurants. Headquartered in Miami-Dade County, Florida, the company was founded in 1953 as Insta-Burger King, a Jacks ...
to Canada with a US$12 billion merger with Tim Hortons
Tim Hortons Inc., known colloquially as Tim's, Timmies, or Timmy's, is a Canadian multinational coffeehouse and restaurant chain with headquarters in Toronto; it serves coffee, Doughnut, donuts, sandwiches, Breakfast sandwich, breakfast egg mu ...
, 5th-largest inversion in history.
* 2015 Medtronic
Medtronic plc is an American-Irish medical device company. The company's legal and executive headquarters are in Republic of Ireland, Ireland, while its operational headquarters are in Minneapolis, Minneapolis, Minnesota. Medtronic rebased to I ...
to Ireland with a US$48 billion merger with Covidien plc, largest inversion in history.
* 2015 Mylan
Mylan N.V. was a global generic and specialty pharmaceuticals company. In November 2020, Mylan merged with Upjohn, Pfizer's off-patent medicine division, to form Viatris. Previously, the company was domiciled in the Netherlands, with principa ...
to the Netherlands in a merger with the international generics division of Abbott Laboratories
Abbott Laboratories is an American multinational medical devices and health care company with headquarters in Abbott Park, Illinois, in the United States. The company was founded by Chicago physician Wallace Calvin Abbott in 1888 to formulate k ...
; first merger of a US corporation with the non-US business of a US corporation.
* 2016 Johnson Controls to Ireland with a US$17 billion merger with Tyco International
Tyco International was a security systems company incorporated in the Republic of Ireland, with operational headquarters in Princeton, New Jersey, United States (Tyco International (US) Inc.). Tyco International was composed of two major busin ...
, 3rd-largest inversion in history.
Aborted
* 2014 Abbvie
AbbVie Inc. is an American pharmaceutical company headquartered in North Chicago, Illinois. It is ranked sixth on the list of largest biomedical companies by revenue. In 2023, the company's seat in Forbes Global 2000 was 74, and rank 89 on the ...
to Ireland with a US$54 billion merger with Shire plc
Shire plc was a UK-founded Jersey-registered specialty biopharmaceutical company. Originating in the United Kingdom with an operational base in the United States, its brands and products included Vyvanse, Lialda, and Adderall XR. Shire was acq ...
, would have been the second-largest inversion in history; blocked by US Treasury.
* 2014 Walgreens
Walgreens is an American pharmacy store chain. It is the second largest in the United States, behind CVS Pharmacy. As of March 2025, the company operated more than 8,700 stores in the U.S.
Walgreens has been the subject of a number of lawsuit ...
to the United Kingdom, as it had already merged with US$16 billion UK-based Alliance Boots; decided to maintain its legal headquarters in the US.
* 2014 Pfizer
Pfizer Inc. ( ) is an American Multinational corporation, multinational Pharmaceutical industry, pharmaceutical and biotechnology corporation headquartered at The Spiral (New York City), The Spiral in Manhattan, New York City. Founded in 184 ...
to the United Kingdom with a US$120 billion merger with Astra Zeneca, would have been the largest inversion in history; Astra rejected Pfizer's GBP£55 per share offer.
* 2016 Pfizer
Pfizer Inc. ( ) is an American Multinational corporation, multinational Pharmaceutical industry, pharmaceutical and biotechnology corporation headquartered at The Spiral (New York City), The Spiral in Manhattan, New York City. Founded in 184 ...
to Ireland with a US$160 billion merger with Allergan
Allergan plc is an American, Irish-domiciled pharmaceutical company that acquires, develops, manufactures and markets brand name drugs and medical devices in the areas of medical aesthetics, eye care, central nervous system, and gastroenterology. ...
, would have been the largest inversion in history; blocked by US Treasury.
UK inversions
Of the 22 inversions executed by UK companies to other jurisdictions, the following are notable:
* 2006 Experian plc to Ireland with a "self-inversion", first ever UK inversion to Ireland.
* 2008 WPP plc
WPP plc is a British multinational communications, advertising, public relations, technology, and commerce holding company headquartered in London, England. It is the world's largest advertising company, as of 2023. WPP plc owns many companie ...
to Ireland, would later return to the UK.
* 2009 Shire plc
Shire plc was a UK-founded Jersey-registered specialty biopharmaceutical company. Originating in the United Kingdom with an operational base in the United States, its brands and products included Vyvanse, Lialda, and Adderall XR. Shire was acq ...
to Ireland, would later merge with Takeda Pharmaceuticals in 2018.
See also
* Base erosion and profit shifting
*Double Irish arrangement
The Double Irish arrangement was a base erosion and profit shifting (BEPS) corporate tax avoidance tool used mainly by United States multinationals since the late 1980s to avoid corporate taxation on non-U.S. profits. (The US was one of a sm ...
*Tax haven
A tax haven is a term, often used pejoratively, to describe a place with very low tax rates for Domicile (law), non-domiciled investors, even if the official rates may be higher.
In some older definitions, a tax haven also offers Bank secrecy, ...
*Conduit and Sink OFCs
Conduit OFC and sink OFC is an empirical quantitative method of classifying corporate tax havens, offshore financial centres (OFCs) and tax havens.
Traditional methods for identifying tax havens analyse tax and legal structures for base eros ...
*Ireland as a tax haven
Ireland has been labelled as a tax haven or corporate tax haven in multiple financial reports, an allegation which the state has rejected in response. Ireland is on all academic " tax haven lists", including the , and tax NGOs. Ireland does no ...
Notes
References
Sources
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External links
Tax Inversions
Zachary Mider, Bloomberg Special Reports, 2015 '' Pulitzer Prize for Explanatory Reporting''
Tax Inversions
Reports by the Financial Times
The ''Financial Times'' (''FT'') is a British daily newspaper printed in broadsheet and also published digitally that focuses on business and economic Current affairs (news format), current affairs. Based in London, the paper is owned by a Jap ...
{{Tax resistance
Corporate taxation in the United States
Corporate taxation in the United Kingdom
Corporate tax avoidance
Tax inversions