Separate legal duration from tax exemption
South Dakota removes a traditional vesting constraint; federal GST treatment still requires a transfer-by-transfer record.
SDCL § 43-5-8 states that the common-law rule against perpetuities is not in force in South Dakota. A conforming instrument can therefore operate without the traditional lives-in-being plus twenty-one-years boundary. The statute does not require permanence, override a written termination clause, or make every asset suitable for indefinite retention.
Federal chapter 13 separately governs generation-skipping transfer tax, exemption, and inclusion ratio. Identify the transferor, taxable event, valuation, allocation, effective date, and later additions. A zero-inclusion-ratio share, partially exempt share, and nonexempt share require different administration even if each uses identical South Dakota duration language.
State duration: SDCL § 43-5-8. Federal overlay: 26 U.S.C. chapter 13, including §§ 2631 and 2642.