By their first assignment of error, appellants contend the trial court erred in the denial of their motion to dismiss on the ground that the petition was not signed. Appellants also contend that the trial court was without jurisdiction in that the petition was neither signed nor verified.
The appellee admits that the petition is neither signed nor verified, but insists that appellants suffered no harm by lack of the petitioner’s signature on the petition and that the lack of a verification is immaterial. Further, that the issue of verification was waived by appellants by their failure to raise it before the trial judge. We disagree.
In the absence of a statutory requirement or rule of court to the contrary, it is ordinarily not necessary to the validity of a petition that it be signed or verified. See State v. Higgins, 266 N.C. 589, 146 S.E. 2d 681 (1966) (affidavit referred to in warrant charging defendant upon information and belief with assault is not defective because affiant did not subscribe the affidavit); Alford v. McCormac, 90 N.C. 151 (1884) (affidavit is valid despite lack of affiant’s subscription if the oath was administered by one authorized to administer oaths).
On the other hand, where it is required by statute that the petition be signed and verified, these essential requisites must be complied with before the petition can be used for legal purposes. See Alford v. McCormac, supra. Without compliance, the petition is rendered incomplete and nonoperative. See In re Colson, 14 N.C. App. 643, 188 S.E. 2d 682 (1972) (juvenile delinquency petition must be signed and verified as “required by law”).
The petition in this case was instituted under Juvenile Code provisions which state in clear and concise terms that the petition *504shall be signed and verified before an official authorized to administer oaths. G.S. 7A-544 provides in pertinent part that when a report of abuse or neglect is received, the Director of the Department of Social Services shall sign a complaint seeking to invoke the jurisdiction of the court. G.S. 7A-561(b) also provides in pertinent part that the complaint should be filed as a petition and the petition shall be verified before an official authorized to administer oaths.
The Juvenile Code requisites that the petition be signed and verified are therefore essential to both the validity of the petition and to establishing the jurisdiction of the court. The primary purpose to be served by signature and verification on the part of the petitioner is to obtain the written and sworn statement of the facts alleged in such official and authoritative form as that it may be used for any lawful purpose, either in or out of a court of law. See Alford v. McCormac, supra at 153. Under the Juvenile Code, these requirements also serve to invoke the jurisdiction of the court.
In the case sub judice, the failure of the petitioner to sign and verify the petition before an official authorized to administer oaths rendered the petition fatally deficient and inoperative to invoke the jurisdiction of the court over the subject matter. It is elementary that the jurisdiction of the court over the subject matter of the action is the most critical aspect of the court’s authority to act. See Shuford, N.C. Civ. Prac. & Proc. (2nd Ed.), § 12-6. Without it the court lacks any power to proceed; therefore, a defense based upon this lack cannot be waived and may be asserted at any time. Id. Accordingly, the appellants may raise the issue of jurisdiction over the matter for the first time on appeal although they initially failed to raise the issue before the trial court. See Real Estate Trust v. Debnam, 299 N.C. 510, 263 S.E. 2d 595 (1980); Bache Halsey Stuart, Inc. v. Hunsucker, 38 N.C. App. 414, 248 S.E. 2d 567 (1978) (an appellate court may raise the question on its own motion).
We conclude that the trial court lacked jurisdiction over the subject matter because the petition was not duly signed and verified as required by law. G.S. 7A-544; G.S. 7A-561(b). Therefore, the order of the trial court must be vacated and the case dismissed.
Vacate and dismiss.
Chief Judge VAUGHN and Judge WELLS concur.