Del. Code tit. 8 § 604
This chapter shall not apply to any individual or groups of individuals within this State who, prior to June 7, 1969, were permitted to organize a corporation and perform personal services to the public by the means of a corporation, and this chapter shall not apply to any corporations organized by any individual or group of individuals prior to June 7, 1969, unless, any such individual, or group of individuals, or any such corporation bring themselves and such corporation within this chapter by amending the certificate of incorporation, in a manner so as to be consistent with all the provisions of this chapter, and by affirmatively stating in the amended certificate of incorporation that the shareholders have elected to bring the corporation within this chapter, or be incorporated initially under this chapter.
8 Del. C. § 604