Lock-up period
A lock-up period, also known as a lock in, lock out, or locked up period, is a predetermined amount of time following an initial public offering where large shareholders, such as company executives and investors representing considerable ownership, are restricted from selling their shares.
Generally, a lock-up period is a condition of exercising an employee stock option. Depending on the company, the IPO lock-up period typically lasts between 90–180 days before these shareholders are allowed the right, but not the obligation, to exercise the option.
Lockups are designed to prevent insiders from liquidating assets too quickly after a company goes public.