 Grab, described as the Uber of Southeast Asia, has confirmed it will list in the US through the largest SPAC deal yet The US40bn deal with special acquisitions company SPAC Altimeter.is worth more than double previous record holder United Wholesale Mortgages US16bn merger in January. SPACs, also known as blank-cheque companies, are set up specifically to find an acquisition and Altimeter had pulled in US4bn from investors including Fidelity International and Temasek from Singapore ahead of the Grab deal. 