Iowa Code § 504.824: Waiver of notice.

1. A director may at any time waive any notice required by this chapter, the articles, or bylaws. Except as provided in subsection 2, the waiver must be in writing, signed by the director entitled to the notice, and filed with the minutes or the corporate records.

2. A director’s attendance at or participation in a meeting waives any required notice of the meeting unless the director, upon arriving at the meeting or prior to the vote on a matter not noticed in conformity with this chapter, the articles, or bylaws, objects to lack of notice and does not thereafter vote for or assent to the objected-to action.