Opinion by
A reversal here is imperative because the court below disregarded the ever increasing trend in procedural law to recognize the real parties in interest as the actual litigants and tо grant them a status as such on the record.
The owners of a property in Pittsburgh appealed from a 1913 triennial assessment to the Board of Property Assessment, Appeals and Review. Plaintiff, a mortgаgee of this property, instituted foreclosure proceedings and purchased the property at sheriff’s sale, at which time she was required to pay all the taxes levied against it for the yeаr 1913. Her counsel thereupon addressed a letter to the Board asking that, in the appeal рroceedings then pending, she be substituted as the new owner of the property, and shortly thereafter she filed with the Board a formal petition to be permitted to intervene and to succeed tо the rights of the former title holders. The Board heard the testimony of witnesses whom she produced, but, so fаr from consenting to accept her as an *51 intervened' or as a successor in interest to tlie prior owners, granted the latter permission to withdraw their appeal. Plaintiff then filed in the Court of Cоmmon Pleas a petition for a writ of alternative mandamus commanding the Board to allow her tо intervene or be substituted in the appeal proceedings and thereupon to continue with the hearings and determine the proper assessment. The court denied the writ, holding that plaintiff had no standing to intervene and that the prior owners had the right to withdraw their appeal.
We are of oрinion that the court was wrong in both of these conclusions. The right of intervention should be accorded to anyone having title to property which is the subject of litigation, provided that his rights will be substantially affеcted by the direct legal operation and effect of the decision, and provided also that it is reasonably necessary for him to safeguard an interest of his own which no other party on thе record is interested in protecting. Equity Rule 25 and Pa. R. C. P. 2327
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are recognitions of this principle. The right of intervention or of substitution especially arises when a beneficial interest in the cause of aсtion is acquired pendente lite, as by purchase of the property during the course of the litigation:
Loughborough, Admr., v. McNevin,
As a corollary to the right of the plaintiff to intervene or be substituted as appellant, it is obvious that the Board should not have allowed the аppeal to be withdrawn at the instance of the prior owners. Discontinuance of an action is always subject to the consent of the court, and it should not be permitted if prejudicial to thе rights of others. As early as 1785 it was held, in a decision of this court which has never been questioned, that a рlaintiff cannot discontinue if he has ceased, by reason of an assignment of the cause of аction, to be the
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real party in interest and if the discontinuance is opposed by the person in whom the beneficial interest has vested:
McCullum v. Coxe,
The order denying the writ of mandamus is reversed and the récord is rеmanded with direction to grant a peremptory writ as prayed for.
Notes
The “action” referred to in Pа. R. O. P. 2327 is defined in Rule 2326, and the “action” referred to in Pa. R. O. P. 2004 is defined in Rule 2001, as “any civil action or proceeding at law brought in or appealed to any court of record which is subject to these rules.”
It is of interest to note that in the
Mesta Machine Company Case
the United States was allowed by the Court of Common Pleas of Allegheny County (91 P. L. J. 343) to intervene in an appеal from this same Board on the ground that it was the actual party in interest since it would have been obliged to reimburse the nominal taxpayer if the assessment were sustained; the right of intervention thus upheld was not passed upon when the case was heard in this court on appeal (
