Five Star Senior Living executives are monitoring the bid price of common shares of the Newton, MA-based company’s stock and considering their options after being threatened with delisting by the Nasdaq Stock Market LLC, or Nasdaq, the company said in a late Tuesday filing with the Securities and Exchange Commission.

The notification came Oct. 22, Five Star said, because shares of the company’s stock for the past 30 consecutive business days had closed below the $1 per common share minimum required for listing. Five Star ended Tuesday with common stock shares trading at 73 cents per share.

The company has until April 22 to regain compliance.

“To regain compliance, the closing bid price of our common shares must meet or exceed $1.00 per common share for a minimum of 10 consecutive business days during the 180 calendar day grace period,” the company said.

If still not in compliance in April, Five Star may be granted another 180 calendar day grace period.

“To qualify for this additional time, we will be required to meet the continued listing requirement for market value of publicly held shares and all other initial listing standards for Nasdaq with the exception of the minimum bid price requirement,” the company said. “If we do not regain compliance within the allotted period(s), including any extensions that we may receive, Nasdaq will provide notice that our common shares will be subject to delisting.”

President and CEO Bruce Mackey said the second quarter had been “difficult” Aug. 9 during the company’s most recent earnings call. He cited “an operating environment that has not been seen in the industry for quite some time” caused by excess units in the marketplace and a decline in the growth rate of adults aged more than 85 years.

“Our efforts over time to create liquidity for the company have helped us navigate this challenging environment. However, we still have a way to go,” Mackey said at the time. “There are some recent positive signs, as new construction starts are down significantly over the past year, and we are encouraged by our recent gains in occupancy in some of our operating segments.”