Corcione said that he returned to fight charges brought against him in July by Prosecutor Nahaniel Murgas.
Corcione reappeared two days after Sixteenth Criminal Court Judge Enrique Pérez ruled that Corcione must be investigated by the Supreme COurt, rather than by the Public Prosecutor's Office. Murgas has appealed that decision.
Critics say the timing of Corcione's decision is suspect, and raises fears of corruption in the judicial system.
Corcione, appearing before the media, said: "I'm here fulfilling my duty as a director of the Panama Canal Authority. I am also doing what I always pledged to do, which is waiting for due process."
He declined to comment on the charges against him, saying: "It is not prudent to talk about the process. That is before the courts, not the media."
Corcione was appointed on the board by then-President Ricardo Martinelli and ratified by the National Assembly five years ago. He stopped attending board meetings two months ago when the charges were announced, saying he was taking a leave of absence.
But the judge's decision, as well as the fact that he could be removed from the board if he continued to miss meetings, apparently spurred his return.