A mark by which the goods or services of any applicant for registration may be distinguished from the goods or services of others may not be registered if it consists of a mark which:
However, nothing in this section prevents the registration of a mark used in this state by the applicant which has become distinctive of the applicant's goods or services. The secretary of state may accept as evidence that the mark has become distinctive, as applied to the applicant's goods or services, proof of continuous use thereof as a mark by the applicant in this state or elsewhere for the five years next preceding the date of the filing of the application for registration.
SDCL 37-6-10