The company said it had notified the Securities and Exchange Commission, which had already been investigating the company's accounting.
Such insiders must notify the Securities and Exchange Commission of any transactions by the 10th day of the month after the transaction.
AT&T said it notified the Securities and Exchange Commission about the problem.
On Nov. 30, a company she controls notified the Securities and Exchange Commission that it planned to sell 200,000 shares of Chantal stock.
In 72 percent of the cases, the companies chose not to give any reason when they notified the Securities and Exchange Commission of the departure.
It has also notified the Securities and Exchange Commission and the United States attorney for the Eastern District of New York.
In late June, Apple said that it had uncovered irregularities with its stock options practices to certain executives and had notified the Securities and Exchange Commission.
Also on Wednesday, Mr. Galvin notified the Securities and Exchange Commission that he intended to exercise these options and sell all 240,000 shares.
The company said it had notified the Securities and Exchange Commission.
He is required to notify the Securities and Exchange Commission if his stake reaches 5 percent.