The real winner in Burger King's deal is...

A drive-through area of a Burger King restaurant in Peoria, Ill.
Daniel Acker | Bloomberg | Getty Images

Burger King's proposed $11.5 billion acquisition of Canada's Tim Hortons may offer big tax benefits to the U.S. fast food chain but the real tax winner is likely to be its controlling shareholder, 3G Capital.

The New York investment firm is not only deferring a capital gains tax hit in the U.S. because of the deal structure, but is also poised to reap a multitude of dividend tax and other benefits by moving Burger King's domicile to Canada, tax experts on both sides of the border said.

Burger King plans to buy the Canadian coffee and doughnut chain in a C$12.64 billion ($11.5 billion) cash-and-stock deal that would create the world's third-largest fast food restaurant group. 3G will own 51 percent of the new firm.

Mark Cuban cuts Burger King some slack
Mark Cuban cuts Burger King some slack

"3G clearly wants to get both the dividends and the capital gains," said lawyer Charles Kolstad at Venable in Los Angeles. "Someone, who clearly knows what he or she is doing spent a lot of time thinking about this. And it's quite clever."

In the deal, 3G has opted for partnership units instead of common shares in the new entity. That move defers the capital gains tax hit it would have faced in the United States had it taken shares.

More significantly, if 3G controls its equity via a holding company in a country that has a tax treaty with Canada, as most tax experts say is likely to be the case, the investment firm will save millions in dividend withholding taxes each year.

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A spokesman for 3G declined to comment on Friday.

A combined Burker King/Tim Hortons will have a much larger float of outstanding shares. That will make it easier for 3G Capital to trim its majority position over time, giving it an exit strategy. The structure also lets the firm escape any Canadian capital gains taxes on share price appreciation, making the potential tie-up one whopper of a deal for the investment firm.

Shares of Burger King and Tim Hortons have soared since word of the deal leaked last Sunday. Burger King stock is up 17.6 percent since the Friday before.

Dividend withholding tax break

Canada does not have a tax treaty with the Cayman Islands, where 3G Capital is incorporated. Tax experts said it is a simple matter for 3G to hold its units via a firm in a country with a Canadian tax treaty, cutting its withholding taxes on dividends paid by Burger King to as low as 5 percent.

Withholding taxes on non-resident shareholders in a Canadian firm can run as high as 25 percent, while similar dividend taxes for non-resident investors in U.S. companies can hit 30 percent.

The differential in the dividend withholding tax rate clearly was a factor in the deal structure, Kolstad said.

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"The ability to be able to re-route things through a treaty jurisdiction and cut your withholding tax rate from 30 percent down to 5 or 10 percent is huge,'' said Kolstad in L.A.

U.S. politicians have criticized the deal as a tax dodge by Burger King.

It is clear though that dividends will be a factor. The two firms made dividend payouts of nearly $230 million in 2013.

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"Both companies have had pretty balanced capital structures and capital return policies in the past. And we're going to continue to have that," Burger King Chief Executive Officer Daniel Schwartz said this week, though he declined to give details on size.

—By Reuters