Aldisert, Adams and Rosenn, Circuit Judges.
A 1938 zoning ordinance in the Pennsylvania borough of Fox Chapel providing for a minimum lot size of three acres was amended in 1964 to permit lots of two acres if drawn from a nine acre tract. Appellant owns a parcel of 4.2568 acres. He contends that the ordinance and its amendment prevent his lawful utilization of his land and thus amount to an unconstitutional taking under the Fifth and Fourteenth Amendments. In the district court he unsuccessfully sought a declaratory judgment that the ordinances are unconstitutional. The court granted defendant's motion to dismiss on the ground "that the cause of action was not a case or controversy ripe for judicial determination in that plaintiff has not exhausted his specific administrative and statutory remedies." In the view we take of this case, it becomes necessary only to discuss whether appellant's complaint presented an "actual controversy" under the Federal Declaratory Judgment Act, 28 U.S.C. § 2201.*fn1
Statutory jurisdiction in these proceedings is based on diversity of citizenship, 28 U.S.C. § 1332. The Declaratory Judgment Act itself "is procedural only," Aetna Life Ins. Co. v. Haworth, 300 U.S. 227, 57 S. Ct. 461, 81 L. Ed. 617 (1937);*fn2 by the Act, "Congress enlarged the range of remedies available in the federal courts but did not extend their jurisdiction," Skelly Oil Co. v. Phillips Petroleum Co., 339 U.S. 667, 671, 70 S. Ct. 876, 879, 94 L. Ed. 1194 (1950). Though statutory jurisdiction be present, however, a further jurisdictional inquiry is required to determine whether an "actual controversy" exists. The "word 'actual' is one of emphasis rather than of definition," Aetna, supra, 300 U.S. at 240, 57 S. Ct. at 463. The "controversy" is required by the Constitution, and the statutory language is merely a restatement of the Article III mandate.*fn3
Although this inquiry has commanded the attention of the Supreme Court both before*fn4 and since the passage of the Federal Declaratory Judgment Act, the standards by which cases and controversies are distinguished from claims premature or insufficiently adverse are not susceptible of ready application to a particular case. The considerations, while catholic, are not concrete.*fn5 The Supreme Court itself is not unaware of this problem of definition. In a review of the proceedings after remand in Zwickler v. Koota, 389 U.S. 241, 88 S. Ct. 391, 19 L. Ed. 2d 444 (1967), the Court held that because Zwickler's Congressional candidate, for whom he desired to distribute literature in contravention of the questionable state statute, had, in the interim, been elected to a fourteen year term as a state judge, the First Amendment issue was mooted, and hence no actual controversy existed at the time of the hearing on remand. In Golden v. Zwickler, 394 U.S. 103, 108, 89 S. Ct. 956, 959-960, 22 L. Ed. 2d 113 (1969), the Court observed:
The difference between an abstract question and a "controversy" contemplated by the Declaratory Judgment Act is necessarily one of degree, and it would be difficult, if it would be possible, to fashion a precise test for determining in every case whether there is such a controversy. Basically, the question in each case is whether the facts alleged, under all the circumstances, show that there is a substantial controversy, between parties having adverse legal interests, of sufficient immediacy and reality to warrant the issuance of a declaratory judgment. Maryland Casualty Co. v. Pacific Coal & Oil Co., 312 U.S. 270, 273, 61 S. Ct. 510, 512, 85 L. Ed. 826 (1941).
The Court has, however, continually emphasized the substantial degree of specificity required in declaratory judgment actions. In United Public Workers v. Mitchell, 330 U.S. 75, 89, 67 S. Ct. 556, 564, 91 L. Ed. 754 (1947), in refusing to pass on the propriety of contemplated political activity by government employees challenging the Hatch Act, the Court held that abstract issues do not invoke the jurisdiction of the courts:
As is well known the federal courts established pursuant to Article III of the Constitution do not render advisory opinions. For adjudication of constitutional issues "concrete legal issues, presented in actual cases, not abstractions" are requisite. This is as true of declaratory judgments as any other field.
In Poe v. Ullman, 367 U.S. 497, 81 S. Ct. 1752, 6 L. Ed. 2d 989 (1961), the Court refused the request of two women and a physician to have declared unconstitutional Connecticut's proscription of the use or the dissemination of information concerning the use of birth control devices. The Court cautioned that federal judicial power "is to be exercised to strike down legislation, whether state or federal, only at the instance of one who is himself immediately harmed, or immediately threatened with harm, by the challenged action." Id. at 504, 81 S. Ct. at 1756. Thereafter, the litigants accepted the dare implicit in Mr. Justice Frankfurter's opinion. They opened birth control clinics in New Haven, Connecticut, were arrested, and again posed the constitutional question. The Court met the issue squarely and declared the statute unconstitutional, Griswold v. Connecticut, 381 U.S. 479, 85 S. Ct. 1678, 14 L. Ed. 2d 510 (1965).*fn6
Similarly, the Court dismissed as premature a request by alleged members of the Communist Party that a statute requiring registration statements by the Party on a form prescribed by the Attorney General be declared unconstitutional. In Communist Party of United States v. Subversive Activities Control Board, 367 U.S. 1, 106, 81 S. Ct. 1357, 1416, 6 L. Ed. 2d 625 (1960), the Court ruled that the mere promulgation of the regulation was not enough: "The duties imposed by those provisions will not arise until and unless the Party fails to register. At this time their application is wholly contingent and conjectural."*fn7 When the members subsequently appealed from an order directing them to register under the Act, however, the Court ruled that a declaratory judgment properly would lie. Albertson v. Subversive Activities Control Board, 382 U.S. 70, 86 S. Ct. 194, 15 L. Ed. 2d 165 (1965).
Professor Wright has synthesized the teachings of the foregoing cases and others:*fn8
The Supreme Court has indicated a very marked reluctance to have important issues of public law resolved by declaratory judgments. It has said that declaratory judgment procedures should not be used to preempt and prejudge issues that are committed for initial decision to an administrative body or special tribunal, and warned against grant of a declaratory judgment involving an important question of public law on the basis of a sparse and inadequate record. The Court has also said that questions of scope and constitutionality of legislation must not be decided "in advance of its immediate adverse effect ...