​While Obama slams tax inversions, his donors profit

It's never good to bite the hand that feeds you.

President Barack Obama may be doing just that with his recent campaign against tax inversions, according to a report from Bloomberg News. Some of the people who have worked on recent inversions are also some of his biggest donors, the report notes.

Tax inversions have become a hot-button topic in political and financial circles, with some opponents calling them unpatriotic. The deals happen when an American company merges with a foreign firm, allowing the U.S. company to shift its headquarters overseas and then avoid paying some U.S. taxes. The Obama administration has become increasingly concerned about the strategy, and is considering ways to curtail the tax benefit.

Take Blair Effron, an investment banker who hosted a fund-raising event for Obama in May at his Upper East Side home in Manhattan. A seat at the dinner reportedly cost a minimum of $20,000.

Effron helped raise more than $500,000 for Obama through campaign-donation bundling, Bloomberg notes. But through the banker's work at Centerview Partners, he's connected with one of the biggest tax inversions in the works, Mylan's (MYL) offer to buy generic drugmaker Abbott Laboratories (ABT).

That's because Centerview acted as a financial advisor to Mylan, which plans to create a tax inversion by using the merger to form a new company that will be based in the Netherlands.

Overall, the administration has more than 20 donors who are linked to tax inversions, Bloomberg notes.

"We are not privy to the details of and have no role in individual companies' plans," a White House spokeswoman wrote in an emailed statement to CBS MoneyWatch. "The President has been very clear -- Congress needs to take action to close one of the most unfair tax loopholes that allows companies to avoid paying taxes here at home, and the best way to do this is through business tax reform legislation that lowers the corporate tax rate, closes wasteful loopholes and simplifies the tax code for everybody."

Obama has been publicly speaking out against the strategy, noting earlier this month that his administration is studying whether existing statutes could "discourage some of the folks who may be trying to take advantage" of the ploy.

The White House statement added that the Treasury Department "is reviewing a broad range of authorities for possible administrative actions that could limit the ability of companies to engage in inversions, as well as approaches that could meaningfully reduce the tax benefits after inversions take place."

While the strategy has helped some businesses lower their tax rates, it's costing tax payers plenty. The technique may result in a loss of $20 billion in taxes over the next decade, according to a study from the Joint Committee on Taxation.