@Denise Evans, a few posters have alluded to this but I'm still not sure you've directly addressed it.
Assume Landowner failed to pay 2012 taxes, and the property was sold to the state for taxes in May 2013. In May 2014 Investor purchases a tax certificate. When should Investor receive a tax deed? (See 40-10-29: "After the expiration of three years from the date of the sale of any real estate for taxes, the judge of probate then in office must execute and deliver to the purchaser. . . a deed to each lot or parcel.) Should it be May 2016 (3 years after the state purchased) or May 2017 (3 years after investor purchased).
If Investor receives a tax deed in May 2017, does Landowner still have 3 more years to redeem? (See 40-10-82: "No action for the recovery of real estate sold for the payment of taxes shall lie unless the same is brought within three years from the date when the purchaser became entitled to demand a deed therefor . . ."
It appears to me that 40-10-29 and 40-10-82 effectively create a 6 year redemption period for Landowner. This is because Investor has to wait 3 years for a tax deed, and then Landowner has 3 years after the tax deed is issued in which to redeem. Am I correct?