A term mainly used on the context of employee stock ownership or option programs. An employee might be given equity in a firm but must stay associated with the firm for a number of years before they are entitled to the full equity. This is a vesting provision. It prevents the employee from taking the equity immediately selling it and quiting the job.
VEST
Meaning of VEST in English
Campbell R. Harvey. Hypertextual finance English glossary. Английский словарь гипертекстовых финансов. 2012