S.D. Codified Laws § 12-5-1
A new political party may be organized and participate in the primary election by filing with the secretary of state not later than the last Tuesday of March at five p.m. prior to the date of the primary election, a written declaration signed by at least one percent of the voters of the state as shown by the total vote cast for Governor at the last preceding gubernatorial election, which declaration shall contain:
whereupon the party shall, under the party name chosen, have all the rights of a political party whose ticket was on the ballot at the preceding general election. No signature on a declaration is valid if the declaration was signed more than one year prior to filing of the declaration.
A political party loses the right to participate in the primary election for failure to meet the definition of political party as defined in § 12-1-3.
The national and state chairperson of a recognized political party may request in writing, subscribed and sworn to by each chairperson before any officer qualified to administer oaths and take acknowledgments, to no longer be recognized as a political party. The political party shall also comply with the requirements for dissolution pursuant to chapter 12-27.
SDCL 12-5-1