Investors are not able to buy all of the shares or bonds they want, so underwriters must allocate the shares or bonds among investors. This occurs when a new issue is underpriced or in great demand because of growth prospects.
OVERSUBSCRIBED ISSUE
Meaning of OVERSUBSCRIBED ISSUE in English
Campbell R. Harvey. Hypertextual finance English glossary. Английский словарь гипертекстовых финансов. 2012