It has arranged for outside investors to guarantee Mr. Cohen an undisclosed price for the painting unless another bidder offers even more during the auction an arrangement called a third-party guarantee.

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Although no third-party company can guarantee you the best rate or a glitch free roll out, they can help you avoid the potentially serious issues that companies face when they decide to implement a new software package.

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There is no guarantee that Mr Reeves's pocket map will lead Britain's third party to safety.

ECONOMIST: Bagehot