The defendant Carl Ray Thompson is here seeking a reversal of a decree of specific performance of an “option to purchase” a tract of land in American Fork, Utah. It is the contention of the appellant Thompson that the plaintiff had not exercised its option in accordance with the terms thereof.
Russell Thompson, the father of the named defendants, was the owner of the property in question prior to the events we are here concerned with. One Mackey Boley, a real estate broker, negotiated with Russell Thompson for the sale of the land to the plaintiff. The option was dated March 19, 1969, and contained the following provisions:
The Buyer may exercise this “Option” by notice in writing of intent to exercise *326delivered to the undersigned by registered mail * * * together with a tender of the $5800 balance of the down payment. In the event that this Option is so exercised, the buyer shall be granted 30 days from the date of receipt of intent to exercise to complete the closing of this transaction, including the execution of a promissory note and deed of trust in a form suitable to the seller, and containing the terms as set forth above for the payment of the balance of the purchase price, copies of which forms are attached hereto. * * * [Emphasis added.]
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This Option shall remain in effect for a period of 120 days from the date hereof * * * to and including July 17, 1969.
Russell Thompson died on April 20, 1969, and his sons Reed and Russell A. Thompson were appointed administrators of his estate. The decedent had executed a quitclaim deed on March 3, 1963, conveying the property to his son Carl, who is the appellant here.
On July 17, 1969, Mackey Boley, the real estate broker above mentioned, at the direction of the plaintiff, delivered letters to the homes of Russell A. Thompson, coadministrator, defendant Carl Ray Thompson, and to the attorney representing the administrators of the estate of Russell Thompson, notifying the addressees of the plaintiff’s intention to exercise the option. The letter fixed as a time for closing the transaction on August 15, 1969. The balance of the down payment in the sum of $5800 was not tendered to the defendants in connection with the plaintiff’s exercise of the option.
Before the plaintiff was entitled to a decree of performance it had the burden of showing that it had exercised the option in accordance with its terms. The plaintiff had the burden of establishing that it had paid or tendered the amount specified in the option within the prescribed time.1 It is clear from the record that the plaintiff failed to tender the sum agreed upon within the time specified in the option. It would thus appear that the trial court erroneously granted the decree of specific performance.
One other aspect of the case requires our consideration. It is the plaintiff’s contention here that the appellant, Carl Thompson, has no standing to challenge the findings and decree of the court below. The contention of the plaintiff is that the administrators having elected not to appeal, the decision of the trial court is *327res judicata. The plaintiff made Carl a party to this suit and in the course of the proceedings procured a judgment against him. The rules of procedure provide that an appeal may be taken to this court from all final judgments,2 and we see no reason why appellant here should not be permitted to challenge the adverse judgment entered against him in the court below.
The decision of the District Court is reversed. Appellant is entitled to costs.
CALLISTER, C. J., and HENRIOD, J., concur.. Coombs v. Ouzounian, 24 Utah 2d 39, 465 P.2d 356; Miller v. Carmody, 152 Colo. 353, 384 P.2d 77; Rude v. Levy, 43 Colo. 482, 96 P. 560, 24 L.R.A.,N.S., 91.
. Rule 72, U.R.C.P.