MannKind Corp. on Friday announced that it has received a delisting notice from the Nasdaq stock exchange, as the company has traded below $1 for more than 30 days.

The Valencia biotech failed to properly notify investors of the delisting letter, which was received on Sept. 14. The company should have informed the public within four days of receiving the warning.

To regain compliance under the Nasdaq listing rules, the company has 180 days to raise its stock price at or above the $1 threshold for 10 consecutive days.

Some analysts speculate MannKind will hold a reverse stock split to remedy the situation. However, the company’s cash situation remains dire, and it will now have to expend resources on Nasdaq compliance.

Shares closed down 7 cents, or nearly 10 percent, to 61 cents on the Nasdaq.