"Failure of a company to meet a minimum closing bid price of at least $1 for 30 consecutive trading days can trigger delisting. When this happens Nasdaq issues a deficiency notice to the company. Another action that brings a deficiency notice is a company's failure to file periodic reports by dates specified by the Securities and Exchange Commission."
"After receiving a deficiency notice, a company has 180 calendar days to return to compliance. A company warned about its shares' minimum bid price must achieve a closing price of $1 or more for 10 consecutive trading days during this period. Report-filing offenders must file the required reports, and then must file subsequent reports by the due dates."