SDCL § 61-1-8: Required coverage continues until terminated by law.

As used in this title, the term, employer, includes any employing unit which, having become an employer under subdivision 61-1-4(2), or under any of §§ 61-1-5 to 61-1-7, inclusive, has not, under §§ 61-5-11, 61-5-15, and 61-5-17, ceased to be an employer subject to this title.