The appellees’ motion for rehearing, supported by their own brief and that of amici curiae, presents but little in the form of new cases, reasoning, or logic that was not considered in drafting the original opinion. We see no occasion to depart from our previous decision.

However, since the decision heretofore-rendered has no provision limiting its.. application to future transactions, the decision will operate retrospectively unless, we expressly order otherwise. There is. ample precedent in this jurisdiction that ini tax matters — when a previous decision is. overruled — the new decision be given prospective effect only.' See, O’Malley v. *377 Si ms, 51 Ariz. 155, 75 P.2d 50, 53, 115 A.L.R. 634; Duhame v. State Tax Commission, 65 Ariz. 268, 179 P.2d 252, 259, 171 A.L.R. 684.

In fairness to the parties who relied upon the previous holding of this court — in the Pratt-Gilbert case — that transactions of the character here involved were nontaxable under the Excise Revenue Act of 1935, 'as amended, we now hold that our decision in the instant case be given prospective effect only and it is so ordered.

The motion for rehearing is denied.