The two heirs of the fortune of the late Walter J. Zable, the founder and chief executive of Cubic Corp., are selling about 2.3 million shares of the stock they own, according to a recent securities filing.

Walter C. Zable and Karen Zable Cox together own about 8 million shares of Cubic, with about 5 million of that total owned through several trusts.

The company said in the filing that the sellers will offer the shares at $40.75 per share, which is an 8 percent discount to Cubic closing price of May 15. The sellers will receive all of the proceeds from the stock sale, and none of the funds will go to the company, according to the filing. The money is presumably being used to pay the estate taxes that are due, local sources said.

The 2.3 million shares to be sold amount to about 8.5 percent of Cubic’s total shares outstanding of nearly 27 million.

Zable died in June 2012 at the age of 97. Walter C. Zable is Cubic’s executive chairman of the board. William Boyle is the chief executive officer.

Cubic shares recently traded at $45.83 on the New York Stock Exchange, giving it a market capitalization of $1.2 billion. The 52-week range was $40.61 to $52.53.

— Mike Allen