A backstop guarantor will ALWAYS receive some sort of compensation for taking the risk associated with being the backstop.
Usually this means a breakup fee if the offering is fully subscribed and the backstop is not needed. Other times it means that the backstop acquires equity at a discount.
Think about it...if you're going to be the guarantor of an offering, and the public has rejected that offering because the terms are seemingly not beneficial, wouldn't you demand that your terms are more favorable?
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