Medical device giant Medtronic is now the largest firm to renounce its U.S. tax status as it legally moves operations to Ireland, where taxes are more business-friendly.

The move is part of Medtronic's acquisition of Covidien, a rival health care and medical supply provider, for approximately $42.9 billion in cash and stock, according to a Medtronic press release.

Once the acquisition is complete, Medtronic will be the "world's premier medical technology and services company" the release boasts, adding that the combined firm will have 87,000 employees in more than 150 countries. The new firm, to be called Medtronic plc, will have its legal headquarters in Ireland, but is not abandoning its operations in the United States. Medtronic predicts the companies will yield a combined revenue of $27 billion.

The release restates Medtronic's commitment to the medical device and health care industries, and reveals plans for the company's stateside operations after the acquisition has been finalized. Citing a direct benefit of the new financial structure, Medtronic commits to investing $10 billion in technology over the next 10 years, more than it had planned for pre-acquisition.

Reasoning behind Medtronic's move to Ireland seems to be only financial. While the new Medtronic plc will have its principle executive offices in Ireland, the company will continue to use its Minneapolis, Minn., office with 8,000 employees as its operational headquarters.

Deals like Medtronic's will cost the U.S. $19.5 billion in lost tax revenues, claims a Bloomberg report on the acquisition. These losses are suffered when corporations find ways around the 35 percent corporate income tax in the United States.

Some members of Congress, including Sen. Carl Levin, D-Mich., are pushing to prevent U.S. companies from reincorporating at a foreign address to dodge taxes. Called "inverting," the tax loophole allows U.S. companies who merge with foreign entities to reincorporate in nations with lower corporate taxes. The loophole also allows companies to access and use their overseas earnings without being taxed at U.S. rates.