delivered the opinion of the Court.

The principal question in this appeal is whether a pending action for legal redemption affected the subacquirer of the condominium object of the redemption.

Luis Zalduondo Veve died testate in the year 1954. As his heirs he left his seven children, Milagros, María, Carlota, *5Berta, Diego, and Luis Zalduondo Cruz and Juanita Zal-duondo Diaz. Among the properties of his inheritance there was a rural property of 252.90 cuerdas located in the ward Juan Martin of the Municipality of Luquillo. The property was recorded in the Registry of Property in the name of his seven children in equally undivided shares.

On June 3, 1955 the co-owner, Milagros Zalduondo Cruz sold to Nicolás Iturregui, married to Ana Margarida, her joint-ownership of one-seventh of the undivided share in said property for the price of $7,200. On June 10, 1955, that is, seven days after said sale, the co-owner Juanita Zalduondo Diaz, filed an action against the conjugal partnership Itu-rregui-Margarida, in the Superior Court, San Juan Part, for the redemption of said joint interest. With her complaint she deposited the amount of $7,200, which was the selling price of said parcel and, also, $100 “to cover the expenses of the contract and any other lawful payment made by the purchasers for the sale as well as to cover any necessary or useful expense made on the property sold.” Among other allegations in her complaint she stated:

“In case that the sum of $100 were not sufficient to cover the aforesaid expenses, the plaintiff offers to pay the amount once it is known, and to that effect accompanies the present complaint with a bond to insure that she will deposit said amount.”

On December 22, 1955 the action for redemption was still pending. The defendant spouses had not recorded their undivided interest in the registry, nor had the title been presented for its recording. On that day the spouses Iturregui-Margarida sold to Ramón Agudo Cano and his wife Raquel Baker the condominium object of the action for redemption which was pending.1

*6On January 26,1956 the redeemer requested and obtained from the trial court the substitution of the spouses originally sued, Xturregui-Margarida, for the new acquirers pendente lite, of the undivided joint interest in litigation, the spouses Agudo-Baker as party defendants. On the same date, with the authorization of the court, she filed an amended complaint in which she reproduced the allegations of the original complaint, she alleged the second sale in favor of the new defendant spouses, she stated, that the latter, as well as the original defendants, were persons alien to the community and prayed that the sum of $7,200 be considered as deposited in favor of the spouses Agudo-Baker, and that they be ordered to issue in favor of the plaintiff a public deed transferring to her title of the undivided joint interest which had first been sold by Milagros Zalduondo Cruz to the spouses Iturregui-Margarida.2

*7Agudo Cano answered the amended complaint. He admitted all the allegations in the first, second and third paragraphs of the amended complaint which read:

“1. By deed No. 58 of June 3, 1955 executed before the Notary . . ., Milagros Zalduondo Cruz sold to the defendant spouses all her title, right or share corresponding to her as heiress of Luis Zalduondo Veve, in a property of 252.90 cuerdas located in ward Juan Martin of Luquillo, Puerto Rico, and which is described as follows:

‘Rural: Parcel of land composed of 252.90 cuerdas located in Ward Juan Martin of Luquillo. Bounded on the north and east by Nicolás Iturregui; on the south, by the Land Authority and various parcel owners and on the west by the Hacienda Margarita.’

“2. Said sale was made for the price of $7,200.

“3. After this action was filed, and while it was pending, the original defendants, spouses Iturregui-Margarida sold to the spouses Ramón Agudo and Raquel Baker the share they had acquired as it has been stated in the first paragraph.”

He did not deny — and therefore it should be considered as admitted, pursuant to the provisions of Rule 8(d) of Civil Procedure then in effect — that part of paragraph four which says “The plaintiff is and was co-owner of the described property.”

In relation to the fifth and sixth and last paragraphs, he stated that as they were “questions of law” he had nothing to allege. Those two paragraphs state:

“5. The plaintiff wishes to recover the share sold to the defendants and to that effect she deposited in the Office of the Clerk of this court, the sum of $7,200, purchase price, at the disposition of the spouses Iturregui-Margarida and an additional sum of $100 to cover the rest of the expenses of the contract or any other lawful payment made by the buyers for the sale as well as for any other necessary or useful expense made on the property sold. In case that the sum of $100 is not sufficient to cover the aforesaid expenses, the plaintiff offers to pay the amount once it is known and to that effect jointly with *8this complaint sends a bond to insure that she will pay said amount.

“6. The plaintiff binds herself not to sell the share redeemed within four years.”

Agudo Cano only denied that part of paragraph 4 of the amended complaint which reads:

. . and the original defendants as well as the spouses Agudo-Baker are strangers to the existing community of property.”

His answer alleges as special defenses, in synthesis, that (a) the complaint had “fatally prescribed” in regards to him; (b) the action for redemption could not prosper because, at the time that the action was filed against him, he was not an stranger; and (c) that the plaintiff had not appeared before the court “with clean hands and as a matter of equity her action, untimely filed and in bad faith, should be flatly dismissed.”

After said answer was filed, the plaintiff asked the trial court to render summary judgment in her favor. She based her motion on the “record of the case” and on a sworn statement of the plaintiff in which, among other things, she states:

“4. That neither the defendant spouses Nicolás Iturregui and Ana M. Iturregui, nor the likewise defendant spouses, Ra-món Agudo Cano and Raquel Baker, are, nor have ever been heirs of Luis Zalduondo Veve; not having, therefore, now or at any time, any interest or share in the property object of the causes of action cited in the caption, except the right they acquired from the heirs Milagros, María, Diego, Carlota, Berta, and Luis Zalduondo Cruz.”

As it may be noted, this sworn statement tended to confirm the only fact of the amended action denied by Agudo Cano, that is: that the spouses Iturregui-Margarida as well as the spouses Agudo-Baker were strangers to the community composed by the heirs of Luis Zalduondo Veve.

*9Agudo Cano opposed said motion thus:

“That the Intervener understands that said Motion for Summary Judgment does not lie as to the plaintiff and if it did lie it would be in favor of the Defendant Intervener, Ramón Agudo on the following ground:

“Because any cause of action or right that plaintiff might have had against the intervener has fatally prescribed.”

The motion for summary judgment having been discussed .and submitted for its decision, the trial court determined that it lay and rendered summary judgment for plaintiff which in its dispositive part reads as follows:

“The defendants will execute the corresponding deed in favor •of the plaintiff, transferring to her the share which they acquired of the property described in the caption of the complaint, and which, as provided by our Civil Code, and lawful acts conducted by the plaintiff, was subject to the action for redemption.

“The price of acquisition, for the plaintiff, will be $7,200 plus the expenses of contract and any other legitimate payment incurred by the defendants for the sale, as per paragraph 4 »of the complaint.

“The costs, attorney’s fees for the amount of $800 are imposed on the defendants.”

Agudo Cano appealed from this judgment and in his brief he states the following assignments of error:

“1. The trial court erred in admitting and maintaining the .•action for redemption by the appellee against Iturregui.

“2. The trial court erred in rendering summary judgment.

“3. The trial court erred in substituting the appellants as defendant parties and in rendering judgment against them.

“4. The trial court erred in ordering the substitution and ¿amendments requested by the appellee, permitting that the suit be prosecuted exclusively against the appellants.

“5. The trial court erred in rendering judgment against the •appellants, since they were third parties under the Mortgage Daw or Civil Code.”

*10In the first error the appellants maintain: (a) that the trial court should not have admitted the original complaint against Iturregui because plaintiff did not deposit with the complaint, besides the purchase price, the exact amount of “expenses of the contract,” nor did she bind herself to pay “the useful and necessary expenses” incurred by the buyer; and (6) that said court lacked legal power to consider the complaint in the action of redemption as no “proceedings to avoid litigation” (acto de conciliación) were held as required by the Law of Civil Procedure for Cuba and Puerto Rico in its §§ 1619 and 1620, which should be considered in force. We must decide both matters against the defendants-appellants.

(a) The defendants-appellants, petitioners herein, invoke as grounds for their first contention, the provisions of subd. 2 of § 1616 of the former Law of Civil Procedure which went into effect in Puerto Rico on January 1, 1886 and which in its pertinent part says:

“Section 1616. In order that an action for redemption may be allowed it is necessary:

“2. That the price, if known, be deposited, and otherwise, that security be furnished to do so as soon as the price becomes known.” (Italics ours.)

Said section clearly shows that the only amount which the redeeming co-owner is bound to deposit in order that his action for redemption be allowed is the price of the first sale which gave rise to the redemption, and none other. It is obvious that the requisite of the simultaneous and effective deposit of the purchase price with the filing of the action for redemption, or in the proper case, the deposit of a bond, is not extended in any way to the other additional sums which, as expressly provided in § 1407 of our Civil Code, the redeemer has the duty of “returning to the vendee” and which are: “The expenses of the contract and any other legitimate pay*11ment made by reason of the sale” and “the useful and necessary expenses incurred by the thing sold.”3

As these expenses in addition to the price are ordinarily unknown to the redeemer, the moment for its refund or payment to the purchaser is not concurrent with the filing of the action. Its existence and amount should be alleged and proven by him and their payability and amount fixed by the court in its judgment.4 The redeemer, if action is allowed, is bound, upon complying with the judgment granting the redemption, to previously pay all the expenses determined judicially or by the litigants by common agreement, in order to obtain the transfer of the title to the redeemed thing and the delivery of its possession.5

The deposit of the amount of $100 and the posting of a bond were unnecessary. Pursuant to § 1407, the amount of the expenses of the contract and the other payments and expenses are not part of the stipulated price, as the defendant-.appellant states in his brief.

Neither was it necessary for the redeemer to bind herself in her complaint, to the refund of those expenses and ad*12ditional payments, since said obligation was legally pre-estab-lished. Notwithstanding this, the amended complaint, in its 4th paragraph, has a substantial offering to that respect and the judgment provides, in a certain sense, for its refund.

(6) We could refuse to consider the merits of the" alleged invalidity of the judgment appealed from on the basis-of the absence of the proceedings to avoid litigation (acto de conciliación), because it is a new matter, not raised or discussed at any stage of the proceeding before the trial court. After having answered the complaint, opposed the motion for summary judgment, of having sought indirectly that a summary judgment be rendered in his favor, of raising several incidents in the case, after adverse judgment was rendered and an appeal taken, Agudo Cano raises it, for the-first time, in his brief before this Court.

His insistence in considering it as a jurisdictional matter' or lack of authority by the trial judge to render summary judgment, has prompted us to consider it.

Under the former Law of Civil Procedure, before filing a declaratory action, it was necessary to seek conciliation between the parties before a competent Municipal Judge, except in the suits which it expressly enumerated. The institution of the proceedings to a conciliation, regulated by § § 459 to 479 of said act, responded to the purpose of avoiding suits- and to the desire of giving the litigants the rapid and economic contractual solution of issues susceptible of being decided by the courts and without the need of a public trial. Its origin resides in Doce Tablas, which contained a certain passage which provided that force of law be given to any agreement between the parties reached “on their way to the-trial.” It consisted, considered as a whole, of a conference-granted by law, between the parties who were on the verge-of a controversy for the purpose of letting them explain their respective claims and close with a friendly agreement:. *13or compromise, if they so wished; with this preliminary act it was possible to avoid the litigation.6

Section 460 provided:

“Proceedings to secure a conciliation shall not be necessary for the interposition of actions of tanteo or retracto (redemption), or any other action which is urgent and peremptory in its nature. But if litigation is to be resorted to, the proceedings to secure a conciliation shall be required or a certificate to the effect that a conciliation was attempted without effect.”

The former act, in its §§ 1616 to 1628, regulated the proceedings for redemption. Sections 1619 and 1620 provided :

“Art. 1619. The judge shall admit the complaint and shall order the institution of proceedings for redemption, and the-deposit in the public establishment provided for the purpose of the amount paid, or shall accept security therefor, under his liability, in a proper case, without prejudice to his right to-alter or amend his orders during the pendency of the proceedings, after the presentation of the certificate of the proceedings-to avoid litigation.

“Art. 1620. After the presentation of the certificate of the proceedings to avoid the suit (acto de conciliación), by the plaintiff, the judge shall refer the complaint to the purchaser and shall order him to be summoned, delivering to said purchaser the copies of the complaint and of the documents in the manner prescribed for ordinary actions of greater import.”

*14From the three sections quoted above, it clearly appears that proceedings to secure conciliation were not necessary prior to seeking the redemption although its ulterior course he subordinated to the compliance with said formality.

When General Order No. 118, Series of 1899, approved August 10, 1899 went into effect, it was provided in its § 9 that civil justice and civil procedures of all classes will be administered “under the forms and procedure established further on in this general order.” Notwithstanding the fact that several procedural matters regulated by the former Law of Civil Procedure were declared to remain in force, said General Order did not authorize the continuation of the effectiveness of the conciliation proceedings as an indispensable prerequisite to litigate before the courts created thereby.7 Our Code of Civil Procedure of 1904 did not authorize them either. And much less our rules of civil practice of 1943 and 1958.

In Burgos v. Báez, 17 P.R.R. 599, 602 (1911), we said on this point:

“On April 18, 1901, the date on which it is alleged that the proceedings for conciliation were held, General Order No. 118, series of 1899, which had fundamentally changed the civil procedure in Porto Rico, was already in force. The preliminary proceedings for conciliation became unnecessary for the institution of civil actions, and the provisions of the old Law of Civil Procedure upon the subject were virtually repealed.

“Such being the case, the proceedings for conciliation alleged to have been held in this case have no legal importance as such, and it is unnecessary to find out whether or not the same were held in accordance with all the requirements of the law. . . .”

It is true that in subsequent decisions we have declared valid in Puerto Rico several provisions of the former Law of *15Civil Procedure referring to actions for redemption, particularly those sections which establish the prerequisites or conditions precedent for attempting such action.8 But we have done so on the principle that they are really substantive provisions, essential or fundamental to the right of redemption, which has long been recognized by our Civil Code, such as those which require the filing of the complaint within nine days, the deposit of the selling price and the promise of the co-owner not to sell for four years, contained, respectively, in paragraphs 1, 2 and 5 of § 1616 of said adjective law.

Since 1899 no civil procedural system adopted or created in Puerto Rico has revived the conciliation proceedings as a prerequisite to the filing of all classes of suits. We could say, however, that the only analogous precedent established by our Legislature is the “preliminary hearing or act of conciliation,” in certain divorce actions when there are minor children, provided by Act No. 118 approved May 7, 1942, and which amended § 97 of our Civil Code. Perhaps also there might be a similarity, because of their purpose, between the old acts of conciliation and those effected in relation to the industrial and agricultural controversies between employees and employers by the mediation and conciliation services or commissions created by Acts No. 36 of June 3, 1919, No. 15 of April 14, 1931 and No. 144 of May 13, 1943.

Ordinarily, no notice need be given here to the defendant before filing a suit against him. The filing of the complaint is sufficient notice if it were necessary.9

In González v. Godreau et al., 21 P.R.R. 147 (1914), the appellee alleged that the action for legal redemption in joint-*16ownership did not state facts sufficient to constitute a cause of action “because, as it is necessary that every complaint should allege the existence of a right and its infringement by the defendant in order that the court may grant the proper remedy, it should have been alleged that the plaintiff tendered to the defendants the purchase price and the other expenses referred to in section 1421 [now 1407] of the Civil Code within the nine days allowed by the statute for the redemption and that the defendants refused to accept the same.” As to this contention we said at p. 149:

“In regard to the first point, we will say that the statute contains no provision requiring the joint-owner who seeks to redeem the property sold to tender to the purchaser the purchase price and the other expenses referred to in the code in order to bring an action to enforce his right of redemption. The right to redeem the joint-interest sold to a third person does not arise because the vendee may have refused to accept the tender of the purchase price to him by the redeemer but from the fact that the sale was made to a third person. To accept the theory of the respondents, the right to bring an action for legal redemption would arise when the purchaser refused to receive the purchase price and not, as provided in section 1427 of the Civil Code, from the time when the sale was recorded in the registry of property, or, if not recorded, from the time the redeemer may have had knowledge of the sale. On the other hand, the time allowed by the statute for exercising the right of redemption is so short that it would not be possible in many instances to locate the purchaser for the purpose of tendering him the purchase price and to bring the action within nine days. Such allegation, then, is not necessary and consequently the fact that it is not made does not render the complaint demur-rable.”

If thereafter we have considered unnecessary any extrajudicial procedure prior to the filing of the complaint for the correct exercise of the right of legal redemption of joint-ownership, we must reject with more reason the idea of reestablishing as a condition precedent to this right or to the *17validity of the procedures in the action, the prerequisite of the extinguished conciliation act.10 On the other hand, and even admitting the validity of the act of conciliation, the defendants have not shown: that they have suffered prejudice because of the omission thereof nor the reason for not requesting it in the trial court. We doubt that in a case like the present one and the other two instituted by reason of the other two sales of joint-ownerships in favor of Agudo Cano, in which the parties have behaved with quite some resentment and unusual vehemence, and have even accused plaintiff of acting in bad faith and of not coming to the court with clean hands, the holding of the conciliation act would have been of any practical use or even an attempt to a friendly agreement in the course of a pretrial conference.

II

It is alleged in the second assignment that the trial court erred in rendering summary judgment because: (a) Neither Rule 56 nor any of the other Rules of Civil Procedure is applicable to the action for redemption but only the Law of Civil Procedure of 1881 (sic) in that part relating to the redemptions; (6) if they are applicable, there was a con*18troversy as to appellee’s offer not to sell the redeemed undivided interest for four years, which should have been supported by the presentation of the corresponding evidence; and (c) the defense of estoppel raised another controversy which did not permit that judgment be rendered. The three grounds lack merit.

The Rules of Civil Procedure of 1943, in force when the action for redemption was commenced and decided, provide in Rules 1, 2, 81 and 86, insofar as pertinent, as follows:

“Rule 1. Scope of Rules

These rules govern the 'procedure in the courts of justice of Puerto Rico in all suits of a civil nature, as provided in Rule 81. . . .”

“Rule 2. One form of action

There shall be one form of action to be known as ‘civil action’.”

“Rule 81. Applicability in general

(a) To What Proceedings Applicable. These rules shall be applicable to all ordinary civil actions and to all proceedings for mandamus, injunction, interdict for the retention or recovery of the possession of real property, intervention {tercería), and enforcement of homestead claims.”

*19“Rule 86. Effective date

These rules will take effect on September 1, 1943. They govern all proceedings in actions brought after they take effect. . . .” (Emphasis added.)

The action for redemption being in Puerto Rico an ordinary civil action, it is clear that its prosecution had to be governed by the proceeding specified by these rules and by our Code of Civil Procedure of 1904 in all that was not contrary thereto. We decided in Rivera v. District Court, 68 P.R.R. 625, 628 (1948) :

“. . . The adjective law, or more specifically, the Code of Civil Procedure and the Rules of Civil Procedure, when applicable, have the force of law and those who resort to the courts to seek a relief are bound to follow them while they are in force.”

By provision of the act which vested power in this Court to “regulate judicial proceedings in all the courts of Puerto Rico for the purpose of simplifying them and promoting the prompt administration of justice” — Act No. 9 of April 5, 1941 — such rules would not repeal, enlarge or modify the substantive rights of the litigants. Thus remained in effect the former Law of Civil Procedure provisions whose substantive character we had recognized, among others, some of the prerequisites required by its § 1616 to allow the actions for redemption. One of the grounds being that the redemption, because of its priviledged nature, limiting the power of the purchaser to dispose of the property and which sometimes is considered as an institution disturbing the right of contracting freely, is not an absolute right which can be separated from its exercise, but that, on the contrary, is subordinated to the latter, causing its effectiveness to depend on the special circumstance that it may be claimed properly and upon compliance with the essential conditions of the right of redemption, among which we find, because of its substantive nature those required by said § 1616 in its paragraph 1st *20• — filing the action within nine days— 11 2d — deposit the price and 5th — compromise not to sell for four years. The procedural requirements contained in the 3d, 4th and 7th para-' graphs of said section have not been recognized by us to be in effect. On the contrary, we have expressly decided that the 3d and 4th paragraphs are not in effect because they are procedural requirements in conflict with our adjective laws.12'

When our legislative bodies have wished to preserve the old juridical institutions of a procedural nature, they have done so specifically, either by following the old text or by adopting it in substance. They did so, among others, with the unlawful detainer proceeding, with the so-called Special Legal Proceedings Act in matters of voluntary jurisdiction and with the injunctions for possession to recover or retain the possession of a real property. Said bodies have not so acted with the special proceedings for redemption contained in Title XIX — §§ 1616 to 1628 — of the former Law of Civil Procedure nor with its other provisions purely procedural. Nor has this Court in the exercise of its powers to adopt rules of procedure done so. The tendency of our rulings in our recent decisions has been towards a uniform procedure whenever possible, in all contentious civil actions. Cf. Andino v. Fajardo Sugar Co., 82 P.R.R. 81 (1961).

We should, therefore decide, and we so decide, that Rule 56 of the Rules of Civil Procedure of 1943, as well as all said rules, were applicable to the action for legal redemption filed on June 10, 1955 by the redeemer.13

*21Appellant herein argues that the promise not to sell for four years stated in the complaint created a controversy by itself because it should have been implemented by' the appellee “by her formal consent in court.” Again we disagree on this point.

In her original as well as in the amended complaint the redeemer stated:

“6. The plaintiff binds herself not to sell the redeemed share for four years.”

In her testimony which she attached or offered with her motion for summary judgment, she stated under oath that “she reproduces by reference and makes part of the present testimony all and every one of the allegations included in the three actions of the above-captioned cases.”

In his answer Agudo Cano did not allege anything contrary to the obligation assumed by the plaintiff in her complaints “not to sell the redeemed share for four years.” He simply stated that he had nothing to allege in regards to that promise because it constituted a conclusion of law. In his opposition to the motion for summary judgment he did not allege that it did not lie because said promise created a' controversy which had to be implemented by evidence, as he now does, in his brief before us.

All that the 5th paragraph of § 1616 requires is:

“That the cotenant bind himself not to sell his interest in the property he redeems for four years.”

Redemption should not be exercised for speculative purposes. One of its purposes is to eliminate common ownership, which as Escriche says in his Dictionary, “is usually a perennial source of discord.” As means to avoid speculation; the redeemer, prior to 1855, was requested an oath to the effect that he wanted the property for himself and it was not *22redeemed for speculative purposes. That measure and others were incorporated to the former law of procedural to insure the compliance with the restriction against transfer for those four years. Following previous decisions we decided in Noble v. Rodríguez, supra at 456-57, that the complaint must allege that the redeemer binds himself not to sell.14

The appellant did not attack the promise on the ground that it was false or deceitful or because there existed an speculative purpose. We repeat, he merely stated that he had nothing to say against it because it was a conclusion of law. As we understand what constitutes a conclusion of law, we cannot accept that the simple declaration of a promise not to sell may be considered thus. That position of the defendant did not create controversy in regards to the promise not to sell contained in the complaints. On the other hand, if the assumption of that obligation is a substantive requirement necessary in that action, the manner in which the same was contracted is correct. Under the circumstances of the case at bar we see no need of implementing in court, an obligation already duly contracted. It is true that the judgment made no provision in that regard. But that does not preclude us from modifying it properly.

We find no merit in the appellant’s allegation about the ineffectiveness of the deposit of the price on the basis of the possibility that the redeemer may withdraw the amount thus deposited. Once the price is deposited it may not be withdrawn from the court unless the redeemer runs the risk of having his action dismissed. It can not be withdrawn, *23without giving the other party in whose favor it has been deposited, an opportunity to be heard.

Neither did the alleged defense of estoppel create a controversy in regards to the action for redemption. In the first place, the facts upon which said defense rests took place after the action was filed; in the second place, those facts are not related to the undivided interest object of the redemption action, but they refer to the alleged “conversations” that Agudo Cano had “with the plaintiff to acquire by purchase the undivided interest . . . she has in the property”; in the third place, the acts performed by Juan R. Zalduondo Grier are not acts of plaintiff herself; nor was it alleged that she knew them nor that she made the defendant believe in the veracity thereof.

hH hH

In their third assignment the appellants maintain that the trial court erred in substituting the appellants as defendant party and in rendering judgment against them because (a) the complaint against Iturregui did not state facts constituting a cause of action, and (b) because said complaint had lost all effectiveness at the time of the substitution of the defendants and said substitution was made untimely.

The original complaint is sufficient at law. Pursuant to our well-settled case law all the circumstances and facts necessary for the action for legal redemption were alleged.15 It was filed on the seventh day counted from the first sale and the total deposit of the selling price was made that same day.

Although the plaintiff did not act with the due diligence in the proceeding in failing to summon promptly the original defendant, the truth is that the action did not lose its effectiveness on that account, as the appellant alleges. *24Its prosecution was always pending,16 and appellant himself accepted, as we already stated, that it was pending when he purchased from Iturregui.

Whether it was an amended or a supplemental complaint, the truth is that a new cause of action was not exercised therein, but the same and original cause of action in which, and because of the second sale to Agudo Cano, the court ordered that the original defendant be substituted by the new acquirer. The sale which gave rise to the exercise of the right for redemption was the first and not the second sale. The action having been exercised within the period of nine days, the law does not require that successive purchasers be joined as defendant parties within a new period of nine days counted from the date of each subsequent transfer.

Whether the action had lost its effectiveness, whether the substitution was correctly or incorrectly made or whether instead of an amended complaint a complementary or supplementary complaint should have been filed, are circumstances which, because of the action of Agudo Cano himself, ceased to have importance, if they ever had any. Notwithstanding the trial court’s order naming him and his wife as the only defendant parties in substitution of the original ones, he requested the court that he be permitted to intervene, alleging among other things and praying as follows:

“4. That your 'petitioner is at present owner of the joint interest tohicli the defendant Nicolás Iturregui had in said property and therefore any judgment rendered in the case may affect him adversely in regards to the title over the j oint interests object of the redemption in this case.

“5. That your Intervener has a good and just defense in its merits in the main action since inasmuch as it refers to him it has fatally prescribed.

“Wherefore the Hon. Court is prayed to authorize your petitioner to intervene as a defendant in this action and be con*25sidered as such, and be permitted to file the allegations which are attached to this motion.” (Emphasis added.)

Leave to intervene as a defendant was granted and as such he filed his answer to the amended action. The only thing he did not admit in the same, as we said before, ivas the condition of stranger by Iturregui at the time he bought from him, that is, on December 22, 1955.

The extinctive prescription which the appellant invoked can not prosper or constitute an estoppel to the summary judgment because said defense is based on a false premise. As it is stated, when by judicial order rendered in the action for redemption he substituted Iturregui as the defendant and an amended action was filed by reason of the sale pendente lite in his favor, a new action for redemption was commenced against him, and since at that time there had elapsed “50 days after the Iturregui-Agudo sale, 43 days-after the presentation by Agudo of his title, and 14 days after its final registration . . . the procedural efforts of the appellee tending to establish a new complaint, the same would be fatally defective as it was filed out of time.”

The appellant forgets that legal redemption is given in favor of a co-owner against a stranger who has bought from another co-owner, but not in relation to subsequent sales executed between strangers and that pursuant to ■§ 421(2) of the Code of Civil Procedure, the judgment is “in respect to the matter directly adjudged, conclusive between the parties and their successors in interest by title subsequent to the commencement of the action.” And he was not only an assignee or purchaser pendente lite, but he was the defendant against whom the action was actually litigated. It was not a new and different action of legal redemption; it was the same one already commenced which was properly continued, within the nine days counted from the date of the first sale by Milagros Zalduondo Cruz to Nicolás Iturregui.

*26IV

The trial court did not err in allowing that the suit be maintained against Agudo Cano and his wife, eliminating Iturregui from the same.

While the main action was pending, the assignment of the interest that Iturregui held in the joint interest redeemed, took place. Said transfer pendente lite did not extinguish, terminate or cause the abatement of the action. It continued or subsisted notwithstanding the new change of title holder, invoking a right granted by law and timely exercised. The claim to the undivided share did not vanish at the moment of the second sale. Under the provisions in force at that time of § 69 of the Code of Civil Procedure and Rule 25(c) of 194317 and our decisions in Rivera v. Central Pasto Viejo, Inc., 44 P.R.R. 504, 506 (1933); Pérez v. Díaz, 41 P.R.R. 730, 731 (1931) and Arrache et al. v. Carlsson, 33 P.R.R. 243, 245 (1924), the redeemer could choose to continue it against Iturregui, bringing Agudo Cano into the trial to be heard, of course, or to ask that the former be substituted for all purposes by the latter. With the court’s leave she chose the substitution.

By reason of that substitution the original defendant was eliminated from the suit. If Agudo Cano chose by his own will to occupy Iturregui’s place, and, as he stated in his petition for intervention, “is at present the owner of the joint *27interests which the defendant Nicolás Iturregui had in said property,” he having lost any immediate or mediate relation with the thing sold to such a degree that his power as owner over said joint interest are absolutely and definitively exhausted; if because of said unconditional transfer “The vendee substitutes the vendor in all his rights and actions,” as § 1400 of our Civil Code prescribes, and if the purpose of the redemption is no other than the granting of the title in favor of the prevailing redeemer and the material delivery of the possession of the joint interest, object of the same, which he now enjoys, we see no reason for keeping Iturregui, who can no longer transfer a title which he does not have nor deliver a possession of a right which he does not enjoy, as a necessary party in the action for redemption. The trial court was in a position to reach a complete solution to the controversy without Iturregui’s presence and the judgment may be duly executed without his intervention.

It is true that the Supreme Court of Spain has decided in Judgments of October 11, 1905 and June 8, 1906 that the action should be directed against the original buyer and against the subsequent one. However, in its Judgment of April 28, 1953, among other things, it held:

“(3) If the first purchaser should alienate the property object of the redemption before the latter has taken place, he has lost the property and lacks status and right to transfer it to the redeemer claiming it, without being able to divest the new purchaser of his title without being heard and defeated at trial. (4) The purpose of the redemption, as the real action it is, consists in obtaining the ownership of the property enjoyed wherever it may be, so that the last acquirer, in case of successive ones, be bound to execute the deed of subrogation required by the redemption. (5) The nature of the legal redemption and the purpose of social interest for which it was instituted, do not permit that the exercise of the action which accrues be satisfied in any other manner than by the actual delivery of the thing redeemed.” Judgment of the Supreme Court of Spain of *28April 28, 1953; 42 Revista, General de Legislación y Jurispru-dencia 111 (1953).”

If the sale to Agudo Cano had not been absolute and unconditional, as for example, if Iturregui had only transferred the beneficial ownership retaining the legal ownership or any other power or right of disposition or guarantee, Iturre-gui, would have clearly remained connected with the redeemed thing and his elimination from the suit could not have been decreed.18

The appellant does not show that by Iturregui’s elimination he was caused any prejudice, nor that the trial court committed an injustice. Upon demurring to the motion for summary judgment he did not allege that Iturregui’s presence at the trial was necessary in order that it be decided. The fourth error assigned was not committed.

*29Y

Did Agudo Cano acquire the condition of third-party mortgagee? This is the most serious question presented in this appeal. If he acquired it in conformity to the attendant circumstances of fact, and to our mortgage law applicable, the redemption commenced on June 10? 1955 does not affect him and the judgment rendered should be reversed. Otherwise we must uphold it.

Let us return to the facts. One June 3,1955 the property belonging to the seven Zalduondo Cruz and Zalduondo Diaz brothers and sisters appeared recorded in their names, in equal undivided shares, in the Registry of Property and by hereditary title. On said date, the co-owner, Milagros Zal-duondo Cruz sold her joint interest of one seventh to Nicolás Iturregui and his wife Ana Margarida. On June 10, 1955 the co-owner Juanita Zalduondo Diaz files an action for legal redemption against the spouses Iturregui-Margarida. On *30December 22, 1955, while the action for legal redemption was pending and without title of purchase of the joint interest granted in favor of the spouses Iturregui-Margarida having been recorded in the Registry (nor had it been presented for registration), these defendant-spouses sold to Ramón Agudo Cano and his wife Raquel Baker, the joint interest object of the action. Agudo Cano presents the title held by Itu-rregui, his predecessor at law, for registration, and also that of the new sale in his favor, on December 29, 1955, that is, seven days after the second sale. On January 26, 1956 the plaintiff requests and the court so orders, that the original defendants be substituted as such defendants by the subac-quirers, the spouses Agudo-Baker. On the following day, January 27, 1956, the first sale to Iturregui as well as the second sale by him to Agudo Cano are recorded in the registry.

Let us turn now to the applicable law. Among the causes for the annulment of the sale is the legal redemption. — Section *311395 of the Civil Code.19 This is the right to be subrogated, with the same conditions stipulated in the contract, in the place of the person who acquires a thing by purchase or in payment of a debt. — Section 1411 id.- — The right of subrogation, or of preference or acquisitive priority is granted to the co-owner of a common thing when the share belonging to the rest of the co-owners or to one of them is sold to a stranger. —Section 1413.

With respect to legal redemption our Civil Code contains no provision in case of successive sales, it provides for the case when only one act of alienation of ownership has taken place. However, in regards to the conventional redemption it provides in its § 1399, that the action may be brought “against every possessor whose right arises from that of the vendee, even though in the second contract no mention should have been made of the conventional redemption; without prejudice to the provisions of the Mortgage Law with regard to third persons.”

Our Mortgage Law in its §§ 36 and 38 insofar as pertinent, provides:

*32“Article 36. — Rescissory and resolutory actions shall not lie against third persons who have recorded the deeds of their respective interests in accordance with the provisions of this law.

“Article 38. — As a consequence of the provisions of article 36, no instrument or contract shall be annulled or rescinded to the prejudice of a third person who shall have recorded his interest, for any of the following causes:

“1. ..

“2. On account of legal redemption (retracto) in a sale or the right to acquire for the amount bid in emphyteusis.”

Muñoz Morales, commenting the effects of the action for redemption in regards to third persons, states the following in I Lecciones de Derecho Hipotecario 248:

“As it may be noted in the text of the cited articles (§§ 1020, redemption by coheirs; 1412, redemption by co-owners; 1413, redemption by adjoining owners; and 1529 and 1530, right to pre-emption and redemption in the emphyteusis), these are conditions or better still, legal remedies which are not explicitly stated in the Registry; and in this particular, Morell says, referring to donations where the legal criterion in these and other cases is always the same, that it is not sufficient that a specific section of a statute grants the right to rescind, or resolve or revoke; whether the action of the law or of the will is exercised, it does not prejudice third parties, if the cause is not explicitly stated in the Registry and in its timely registration.” 20

*33However, the Civil Code in its § 1414 modifies the mortgage criterion, when it provides that the legal redemption may be exercised within the nine days “counted from the entry in the registry.” Thus the first purchaser as well as the subacquirers who have recorded their titles within those nine days after the recording of the first sale will be affected by action of redemption filed within those nine days. They will not be if once the first acquisition is recorded the subsequent purchasers have acquired and recorded their titles after those nine days, even when the action of redemption has been filed within said period against the first purchaser. Of course, if the redeemer was cautious and he timely obtained the entry of the notice of lis pendens in the registry pursuant to $ 91 of the Code of Civil Procedure, or the cautionary notice of his claim, pursuant to § 42 of the Mortgage *34Law, or the effectiveness of judgment by means of the prohibition to alienate, said subacquirers shall not be able to oppose the redemption on the ground that they were third-party mortgagees.21

Now then, Ramón Agudo Cano, his wife Raquel Baker and the conjugal partnership composed by them, besides being strangers to the community Zalduondo Cruz and Zalduondo Diaz, as were their predecessors in title, the spouses Iturregui-Margarida, do not have in regard to the redeemer the standing of a third-party mortgagee nor are they entitled to any registration.

Agudo Cano did not acquire his title over the joint interest redeemed from any person who had recorded it in the Registry. The transfer in his favor was made on December 22, 1955. At that time not even the sale of Milagros Zalduondo Cruz in favor of Iturregui had been presented for registration *35and the title owner of the joint ownership, according to the Registry, was Milagros Zalduondo Cruz. Furthermore, Agudo Cano and his wife were made defendant parties in the action before their title was recorded.

We have repeatedly held that a person who has acquired title directly from one who at the time of its execution does not appear in the Registry to have a right to execute it is not a third-party mortgagee.22

Agudo Cano may be considered a third party under the Civil Code who could not acquire any more rights than those held by Iturregui, his predecessor in title.

When Iturregui acquired his title over the joint ownership, he knew from the entries in the Registry that the other joint interests in the property belonged to the other brothers and sisters of his transferor, among them, Juanita Zalduondo Díaz and that each one or all of them had a preferred right to acquire it. Iturregui did not seek registration protection for his title, although the Registry cautioned him when he bought it, as to the community condition of the property. He had to realize the menace or possibility of a resolutory action which the law recognized to the other co-owners and weigh properly the insecure nature of the right which he was acquiring. The right of property transferred to him on June 3,1955 in the joint-ownership, while the right of redemp*36tion remained unextinguished, lacked juridical firmness, it was revocable and his freedom to dispose of the property was tied or subject to the contingency of the action of redemption, not by a single co-owner but by the six of them. In said .situation in any sale made by Iturregui the purchaser also acquired under the caution of a resolutory condition.

The possibility of exercising the redemption became a reality on the following June 10 when the plaintiff complying with all the necessary legal requisites, filed her action against Iturregui. Said right having been exercised timely and properly, and stemming from the execution of the first sale, the possibility of Iturregui’s right acquiring firmness had greatly diminished. Said exercise rendered the first sale in favor of Iturregui void, since in a last analysis, in the redemption the purchaser seems to have acted as a representative of the redeemer. The obstacle for the legal consolidation of his title had been raised by the will of a co-owner. If Iturregui merely had an unstable or revocable title he could not transfer an irrevocable, firm or better juridical title to Agudo Cano. The temporary revocability of Iturregui’s title backfired in the act of the second alienation.

The former purchased without his vendor having recorded his title. The registration condition for him at the time of the purchase was the same that existed when Iturregui acquired, that is, it still clearly appeared from the Registry that the property belonged in common to the heirs of Luis Zalduondo Veve. Iturregui’s condition of stranger to the community had not disappeared. Agudo Cano seemingly did not inquire whether those heirs or any one of them had filed an action of redemption against Iturregui. He purchased while the action of redemption was pending (he so admitted in his answer) and subject to the result of the suit.

The nature of the action of redemption is real. It follows the thing whereever it goes. As stated in 95 Civ. Jur. 929, basically it is nothing more than a revendicatory *37action.23 When Iturregui sold to Agudo Cano, the former lost all immediate or mediate relation over the alienated joint interest. The alienation made by Iturregui to Agudo Cano, as far as they were concerned, is an absolute, unconditional and irresoluble right; by virtue of the contract of December 23, 1955, the condominium can not return to Iturregui’s possession who, upon selling, exhausted the powers that corresponded to him as title owner of the joint interest in litigation. Agudo Cano being the last and present possessor of the redeemed thing, in order to give validity to the right born and exercised in conformity to the law, he is subject, since he acquired, to the consequences of the action which was then pending.

The exercise and validity of the action of redemption is not subject, nor can it yield, to the alleged good faith of a purchaser pendente lite. The purchaser of a part of a thing possessed in common and undividedly by several persons should not presume that the other co-owners have never exercised properly their priority to acquire it. The mere fact of acquiring from the owner who had not bothered to record his joint ownership was sufficient to warn him of a possible *38action of redemption against him. He should have taken into account that he was acquiring an insecure, revocable or resolute right during some time and that he could not simply depend on the good faith that might have been privately suggested to him by his transferor who had not bothered to record or delayed in recording his title timely and thereby avoid a publicity that might prejudice him24 for which reason he should suffer the consequences of his own acts. Juanita Zalduondo Diaz, whose condition of co-owner clearly appeared from the Registry, did nothing more than timely and in due form, and with good success, exercise the right for redemption recognized by our Civil Code and which under the circumstances of the case was as binding on Iturregui and his wife as on Agudo Cano and his wife. The only guarantee he had as a successive acquirer was to be joined as party defendant and be heard in court and he fully enjoyed this protection, in conformance with our civil practice, before the trial court and before us.

Considering all the foregoing we must conclude that at the time summary judgment was rendered, there was no real or genuine controversy as to any material fact of the action of legal redemption of co-owners before the trial court, and that the redeemer had a clear right to obtain judgment as a question of law, it being proper for the court to render summary judgment without the need of an ordinary suit in the merits.25

*39The judgment appealed from should be modified in the sense that it should state that in the public deed executed by the defendants Ramón Agudo Cano and his wife Raquel Baker, or in the proper case, by the marshal of the trial court, conveying the title of the redeemed joint interest to the plaintiff Juanita Zalduondo Diaz, the promise not to sell said joint interest for four years be inserted and that notice of said promise be entered in the Registry of Property so as to give notice to third parties, counting said four years from the entry in the registry of the title granted in favor of the plaintiff and, as modified, it will be affirmed.

The case will be remanded to the trial court so that after hearing the parties it may determine and fix: (1) the expenses incurred in the first contract of sale executed on June 3, 1955 and any other lawful payment made for said first sale, and (2) the necessary and useful expenses made in the thing sold or redeemed, the plaintiff being obliged to pay to the defendant before the execution of the deed or deposit in court at said party’s disposal, the sum of all expenses and payments determined and fixed by the trial court.