South Dakota Codified Laws
Chapter 43 - Products Of The Mind
Section 43-43-5 - Subsequent inventor, author, or composer--Identical production--Rights of respective owners.

43-43-5. Subsequent inventor, author, or composer--Identical production--Rights of respective owners.
If the owner of a product of the mind does not make it public, any other person subsequently and originally producing the same thing has the same right therein as the prior author which right is exclusive to the same extent against all persons except the prior author or those claiming under him.

Source: CivC 1877, §574; CL 1887, §3197; RCivC 1903, §890; RC 1919, §488; SDC 1939, §51.0808.