<Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (September 2014) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (September 2014) (Learn how and when to remove this template message) </Td> </Tr> <P> 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 . </P> <P> Lockups are designed to prevent insiders from liquidating assets too quickly after a company goes public . When employees and pre-IPO investors initially get their shares or options, they sign a contract with the company that typically prohibits trades for the first 90--180 days after a future IPO . When the company is ready to go public, the underwriting bank then reaffirms the existing agreements in new contracts . This helps to ensure the market will not disproportionately increase the supply, which drives prices downward . While lockups used to be simple--usually lasting 180 days for everyone--they have become increasingly complex . </P>

What is a lockup period for an ipo
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