Under the heading Why would a company issue unpaid shares? by Johnathan Korchak
Although unpaid and partly paid shares are far less common than fully paid shares, there are a number of reasons why a company might choose to issue them:
[second-last bullet] In line with a strategy to implement an acquisition or merger of companies.
Under the heading Why would I issue unpaid shares?
Companies may choose to issue partly-paid or unpaid shares for a variety of reasons, including:
[last bullet] As part of a strategy to implement a merger or acquisition.