what is a lock up period 
a lock up period is a window of time when investors are not allowed to redeem or sell shares of a particular investment there are two main uses for lock up periods those for hedge funds and those for start ups ipo s for hedge funds the lock up period is intended to give the hedge fund manager time to exit investments that may be illiquid or otherwise unbalance their portfolio of investments too rapidly hedge fund lock ups are typically 30 90 days giving the hedge fund manager time to exit investments without driving prices against their overall portfolio for start ups or companies looking to go public through an ipo lock periods help show that company leadership remains intact and that the business model remains on solid footing it also allows the ipo issuer to retain more cash for continuing growth 