Del. Code tit. 25 § 81-421
Following execution of a contract of sale by a purchaser, the declarant may not amend any required public offering statement without the approval of such purchaser if the amendment would materially affect the rights of such purchaser. Approval by such purchaser is not required if the amendment is required by any governmental authority or public utility, or if the amendment is made as a result of actions beyond the control of the declarant or in the ordinary course of affairs of the executive board, or if the amendment is required by, or to achieve compliance with the requirements of Federal National Mortgage Association, Federal Home Loan Mortgage Corporation, Federal Housing Authority, Veterans Administration or other governmental agency or their successors.
25 Del. C. § 81-421