Blank cheque companies — initial public offerings for special-purpose companies, or SPACs, that raise cash for acquisition — are enjoying their highest popularity in more than a decade, raising more than $10bn in new listings last year.

Such firms do not have assets or any operating histories. They are largely bets on their executives, who seek to do a deal within a specified time, typically two years. But investors should still be cautious about the structure, according to a review of the companies’ performance by The Wall Street Journal.