Del. Code tit. 18 § 4990
Except as otherwise specifically provided in § 4975 of this title, from the date a plan of conversion is adopted by the governing body of a mutual company until 3 years after the effective date of the plan of conversion, no person shall directly or indirectly offer to acquire, make any announcement to acquire or acquire in any manner, including making a filing with the Department for such acquisition under a statute or regulation of this State, the beneficial ownership of 10% or more of a class of a voting security of the converted stock company or of a person which controls the voting securities of the converted stock company, unless the converted stock company or a person who controls the voting securities of the converted stock company consents to such acquisition and such acquisition is otherwise approved by the Commissioner.
18 Del. C. § 4990