We granted certiorari in Kee v. State Highway Administration, 68 Md.App. 473, 513 A.2d 930 (1986) to review issues involved in the State’s waiver of sovereign immunity as related to the insurance fund administered by the State Treasurer. Instead, we are confronted with an appealability issue that had been obscured by noncompliance with the Maryland Rules concerning returns on the service of process.
Respondents are the plaintiffs in wrongful death, survival, and personal injury claims arising out of a single car, motor vehicle accident. The vehicle had two occupants, who were brothers. While traveling on a state highway on a hill near Braddock Heights, in Frederick County, the vehicle failed to negotiate a curve, went through a guardrail, and plunged down an embankment. The driver died at the accident scene, but the passenger survived. On September 24, 1985, one day short of three years after the accident, respondents filed a complaint against the State Highway Administration (SHA) and against Green Acres, Inc. (Green Acres), allegedly “a Pennsylvania corporation doing business in Maryland” and the party with which SHA had contracted for repair of the guardrail involved in the accident.
In due course the circuit court entered summary judgment in favor of SHA based upon sovereign immunity. On respondents’ appeal the Court of Special Appeals reversed and remanded. Our present concern, however, is with the claim against Green Acres.
The caption of the complaint of September 24, 1985, gave “Butts Street, P.O. Box 687, Sharon, PA 16146” as the address of Green Acres. Part of the initial docket entries for the action state that a summons for Green Acres was prepared for the plaintiffs’ attorney to mail and that a copy was sent to him. The circuit court file contains a copy of *526that summons directed to Green Acres at the Sharon, Pennsylvania address and issued September 25, 1985. That writ of summons remained effective for service made on or before November 25, 1985.1
Plaintiffs’ counsel, as the person to whom the clerk, per Rule 2-112(a), had delivered the summons for service, was thereafter obliged to file a return as required by Rule 2-126. In relevant part Rule 2-126 provides:
(a) Service by Delivery or Mail.—An individual making service of process by delivery or mailing shall file proof of the service with the court promptly and in any event within the time during which the person served must respond to the process. The proof shall set out the name of the person served, the date, and the particular place and manner of service. If service is by certified mail, the proof shall include the original return receipt. If service is made by an individual other than a sheriff, the individual shall file proof under affidavit which shall also state that affiant is of the age of 18 or over.
(d) Service Not Made.—An individual unable to make service of process in accordance with these rules shall file a return as soon thereafter as practicable and in no event later than ten days following the termination of the validity of the process.
(e) Return to Include Process.—A return shall include a copy of the process if served and the original process if not served.
(g) Effect of Failure to Make Proof of Service.—Failure to make proof of service does not affect the validity of the service.
*527Thus, had Green Acres been served in Maryland, e.g., because it did business here as alleged in the complaint, proof of service should have been filed within thirty days after service was effected. Rule 2-321(a). If Green Acres had been served in Pennsylvania, e.g., because service “outside this State [was] authorized by the law of this State” (Rule 2-121(a)), then plaintiffs’ counsel should have filed proof of service within sixty days after service. Rule 2-321(b)(l). If plaintiffs’ counsel had been unable to effect service, then under Rule 2-126(d) he should have filed a return no later than December 5, 1985, i.e., no later than ten days following the termination of the validity of the process.
Plaintiffs’ counsel did none of the above.
On January 17, 1986, the clerk received a letter dated January 14, 1986, from plaintiffs’ counsel which in part read: “Please reissue a Writ of Summons to be served on the Defendant Green Acres, Inc.....” The clerk prepared a new writ of summons dated January 17, 1986, and again directed to “Green Acres, Inc., a Pennsylvania Corporation, Butts Street, P.O. Box 687, Sharon PA 16146.” The docket entry of January 17, 1986, notes in part that the summons was prepared for the attorney to mail and “[c]opy sent.”
This second writ of summons for Green Acres remained effective for service until March 18, 1986, and, had plaintiffs’ counsel been unable to effect service on the party named therein, a return to that effect should have been filed no later than March 28. No return of “non est ” has been filed. Nor has any proof of service been filed.
Summary judgment in favor of SHA was entered April 7, 1986, and plaintiffs’ order for appeal was filed on May 7, 1986. The judgment in favor of SHA had not been certified by the circuit court for immediate appeal under Rule 2-602(b).
At an early stage of the civil appeals process an information report is required by Rule 1023. It asks:
*528Did judgment finally dispose of all claims by and against all parties? If not, please explain why judgment is appealable.
Respondents answered:
It disposed of all claims against governmental defendants; although a private defendant has also been named, plaintiffs have been unable to locate said defendant.
At oral argument before this Court we raised, sua sponte, the appealability issue.2 Set forth below is part of the colloquy between this Court and respondents’ counsel which took place at the beginning of oral argument by counsel for SHA.
THE COURT: Well the question is—were they [Green Acres] served?
PLAINTIFFS’ ATTORNEY: We served somebody up there named Green Acres. It turned out to be the wrong party. In the meantime we’ve been trying to get the name of the correct contractor from the State. The State has refused to provide that____
THE COURT: Well when you found out that you had named and served the wrong party, were they dismissed? Was the party you served dismissed?
PLAINTIFFS’ ATTORNEY: No, your Honor, because frankly there’s still a question in my mind as to whether or not they were in fact the correct party.
THE COURT: So in other words you may have named and served the correct party.
PLAINTIFFS’ ATTORNEY: Right, we may have.
Then, when counsel for the respondents arose to address this Court, we returned to the appealability issue. The relevant part of that colloquy is as follows:
*529THE COURT: Is it clear that you did serve Green Acres?
PLAINTIFFS’ ATTORNEY: No, your Honor. That’s a problem. We served a corporation in Pennsylvania called Green Acres, but they’re a golf course. They’re not a contractor.
PLAINTIFFS’ ATTORNEY: It was my determination that that was the incorrect party and I was hoping eventually through discovery with the State to find out who actually did or did not do this work that had been contracted.
PLAINTIFFS’ ATTORNEY: They’ve never been—we have not served the Green Acres that we’re alleging the argument against.
THE COURT: But you did serve a Green Acres?
PLAINTIFFS’ ATTORNEY: We did serve a Green Acres.
Whether the summary judgment in favor of the State is appealable without a Rule 2-602(b) certification turns on whether Green Acres is a party over whom the circuit court acquired in personam jurisdiction. If the summary judgment disposed of all claims against the only party over whom the circuit court had acquired jurisdiction, then the judgment was final and appealable without certification. See Hardy v. Metts, 282 Md. 1, 381 A.2d 683 (1978); Tidewater Ins. Assocs. v. Dryden Oil Co., 42 Md.App. 415, 401 A.2d 178 (1979). Similarly, under Fed.R.Civ.P. 54(b), from which Maryland Rule 2-602 is derived, a named defendant who has not been served is not a party for the purpose of determining finality of a judgment. See Leonhard v. United States, 633 F.2d 599 (2d Cir.1980), cert. denied, 451 U.S. 908, 101 S.Ct. 1975, 68 L.Ed.2d 295 (1981); De Tore v. Local # 245 of the Jersey City Pub. Employees Union, 615 F.2d 980 (3d Cir.1980); Siegmund v. General Commodities Corp., 175 F.2d 952 (9th Cir.1949). On the other hand, if *530Green Acres has been served, this is a multiple parties case without a final judgment under Rule 2-602, and the appeal is premature.
Respondents’ counsel admitted at oral argument in this Court that he had served the corporation identified by name and address in the complaint. We may act upon concessions and admissions made in oral argument. See J.I. Case Credit Corp. v. Insley, 293 Md. 483, 445 A.2d 689 (1982); Bogley v. Middleton Tavern, Inc., 288 Md. 645, 655, 421 A.2d 571, 575-76 (1980) (per curiam) (deciding Motion for Reconsideration and Clarification). The fact that respondents’ counsel, as the process server, failed to make proof of service as required by Rule 2-126(a) “does not affect the validity of the service.” Rule 2-126(g). In this respect Maryland Rule 2-126(g) tracks Fed.R.Civ.P. 4(g) which also in part provides that “[fjailure to make proof of service does not affect the validity of the service.” The federal rule has been applied literally to recognize a court’s jurisdiction over a party served despite the lack of a return of service. See Davenport v. St. Mary Hosp., 633 F.Supp. 1228 (E.D.Pa.1986); Szabo v. Keeshin Motor Express Co., 10 F.R.D. 275 (N.D.Ohio 1950); Hale v. Morgan Packing Co., 91 F.Supp. 11 (E.D.Ill.1950); Kertes Mfg. Corp. v. Speidel Corp., 93 F.Supp. 483 (S.D.N.Y.1949); Peeples v. Ramspacher, 29 F.Supp. 632 (E.D.S.C.1939). Consequently, this is a multiple party case.
The State, seeking to sustain judgment finality, urges that the lack of any proof of service on Green Acres in the record transmitted by the clerk of the circuit court should be dispositive and submits that a party should not be permitted to undermine facial appealability by admissions at appellate argument. The record in this case, however, is facially ambiguous because the Maryland Rules require either proof of service or a return of nonservice. Indeed, that very ambiguity prompted the question by this Court at argument. One purpose for requiring a return of nonservice is to enable all parties to determine who is in the case and who is not. Thus, the State, as appellee in the Court of *531Special Appeals, also had a stake in avoiding a premature appeal. The State had notice from the circuit court record that a writ of summons for Green Acres had been issued on which no return had been made one way or the other, and the State had notice from Rule 2-126(g) that failure to make proof of service would not affect the validity of service.
There is an additional reason why, in applying Rule 2-602, we decline to limit parties to the action only to those who have appeared or as to whom proof of service has been made. That approach would violate the policy against piecemeal appeals that is the foundation of Rule 2-602. It is rather clear that respondents’ strategy here is to keep the status of Green Acres as fluid as possible. If respondents are able to recover from the State, that may be the end of the action as a practical matter. If respondents do not recover from the State, then, unless respondents completely abandon the action, they would have to address the status of Green Acres. Respondents might attempt to press the claim against the corporation served, or respondents might attempt service on another person, contending that the service previously effected was the result of a mere misnomer and that the person later served should be considered to have been sued as of the date this action was instituted. These kinds of issues could give rise to future appeals. Absent a proper certification, Rule 2-602 is designed to bring all issues in an action up for appellate review in one appeal.
We point out that our holding deals solely with appealability. Whether service on Green Acres of Sharon, Pennsylvania resulted from a misnomer or a misjoinder is not before us and does not affect appealability. On remand, respondents will have to decide whether to seek a Rule 2-602(b) certification or to dismiss the process served.
If a subsequent appeal is taken from a final judgment in this case, and if a petition for writ of certiorari is filed and granted, we shall, at the parties’ option, permit the case to *532be heard upon the existing briefs. Potter v. Bethesda Fire Dep’t, Inc., 302 Md. 281, 487 A.2d 288 (1985).
We have also asked the Rules Committee to consider whether to recommend changing the present Rules in light of the problem revealed by this case.
JUDGMENT OF THE COURT OF SPECIAL APPEALS VACATED. CASE REMANDED TO THAT COURT FOR THE ENTRY OF A MANDATE DISMISSING THE APPEAL. COSTS TO BE PAID BY THE RESPONDENTS.
. Rule 2-113 provides:
A summons is effective for service only if served within 60 days after the date it is issued. A summons not served within that time shall be dormant, renewable only on written request of the plaintiff.
. Appealability is jurisdictional, and we are obliged to raise questions of our own jurisdiction. See Maryland-Nat'l Capital Park & Planning Comm’n v. Crawford, 307 Md. 1, 15 n. 6, 511 A.2d 1079, 1086 n. 6 (1986); Board of Educ. v. Hubbard, 305 Md. 774, 787, 506 A.2d 625, 631 (1986); Washington Suburban Sanitary Comm’n v. Frankel, 302 Md. 301, 307, 487 A.2d 651, 654 (1985); Starfish Condominium Ass’n v. Yorkridge Service Corp., 292 Md. 557, 562, 440 A.2d 373, 376 (1982).