Data provider IHS announced a $13 billion merger Monday that would make it the latest U.S. company to move its headquarters overseas, where it would face lower taxes.

Colorado-based IHS is merging with the smaller London-based Markit in what is known as an “inversion,” in which U.S. companies are bought by or merge with foreign firms to reduce U.S. corporate tax burdens.

The new combined company, IHS Markit, would be based in London and have a corporate tax rate in the low-to-mid-20-percent range. That is far lower than the 35 percent corporate tax rate in the United States. IHS said some key operations would remain in Colorado.

“The rationale for the merger is to create the leading global information services company and benefit from identified cost and revenue synergies,” Ed Mattix, IHS’s senior vice president for corporate communications, said in a statement. “We have adopted a tax structure we think is most appropriate for the combined company.”

Lawmakers have grown increasingly frustrated by the tide of U.S. companies moving overseas to lower their tax rate. In November, pharmaceutical giant Pfizer announced plans to merge with Botox maker Allergan and move its headquarters to Ireland. That deal is expected to save the firm about $35 billion in taxes. Last month, Johnson Controls announced that it would merge with Tyco and move its headquarters to Cork, Ireland. Johnson Controls said the strategy would save the new company — with a market cap of about $36 billion — about $150 million a year in taxes.

Business groups have argued that inversions will continue until Congress lowers the U.S. corporate tax rate, which is the highest in the developed world. But lawmakers are not likely to take action before the presidential election this year, and Republicans and Democrats remain split on the best way to reform the corporate tax code.

The Treasury Department has issued rules meant to stem the tide of companies moving their headquarters overseas. But as structured, the IHS and Markit merger would not be subject to those rules. IHS shareholders would own about 57 percent of the combined company. If IHS had owned 60 percent or more of the combined company, the deal would have been subject to the Treasury Department rules.

And since the company would fall outside those rules, in addition to paying a lower tax rate, IHS Markit would also be able to employ other tax strategies, including a practice known as “earnings stripping” that could lower its taxable U.S. profits. Under such a practice, the U.S. subsidiary of the inverted company would take on loans from its foreign parent company. The interest payments on that debt could then be deducted from the U.S. company’s taxable income.

Two Democratic lawmakers introduced legislation last month to stem that practice, but Congress is not expected to take up the issue anytime soon. The Treasury Department has also said it is reviewing whether it can adopt rules to address the practice.

“It’s always hard to estimate what the tax savings will be, since that depends on what sort of strategies the parties are willing to adopt after the merger,” said Robert Willens, an independent tax expert. “However, it seems a safe bet to predict that the savings will be sizable, since why else structure the deal as a reverse acquisition, in which the smaller company functions as the acquiring corporation?”

The deal comes at a time when corporate inversion has also become a key issue on the presidential campaign trail. Both Democratic candidates, Sen. Bernie Sanders (Vt.) and Hillary Clinton, have lambasted the practice.

IHS, founded in 1959, provides research and analytics to companies in various industries, including the energy sector. Markit provides similar services but focuses on financial firms.

“IHS Markit will continue to have a large presence in the U.S., which has the potential to grow even larger as the newly merged company grows, and we will continue paying applicable U.S. taxes,” said Mattix, the IHS spokesman.

This post has been updated.

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