In probate matters all parties must be served, regardless of whether they are adverse or not; in other appeals generally only adverse parties need be served. As to the question of who is adverse, see, generally, Oil Investment, Inc. v. Dallea Petroleum Corp., 150 N.W.2d 189 (N.D. 1967); Hanson v. Zoller, 174 N.W.2d 354 (N.D. 1970). Parenthetically, it is doubtful that the appeal to the district court would be sufficient even if the statute required service on only adverse parties, since the allowance of the claim of N.F.O. would reduce the amount available for distribution to all the beneficiaries of the will of the decedent, and they therefore would have an interest adverse to that of the appellant N.F.O.

In essence, the real party of interest in these proceedings is Reliance. If Reliance is successful in its appeal such success will be a benefit and not a detriment to AGC — Tex. It is very unlikely, and would require some very unusual events, for AGC — Tex to suffer a greater loss if Reliance's appeal is successful. This court in Oil Investment, Inc. v. Dallea Petroleum Corp., 150 N.W.2d 189 (N.D. 1967), said that an adverse party, within the statute [§ 28-27-05, N.D.C.C.] relating to the service of the notice of appeal, is one whose interest in the judgment appealed from is in conflict with the modification or reversal sought by the appellant. See, Udgaard v. Schindler, 75 N.D. 625, 31 N.W.2d 776 (1948); Smith v. Grilk, 64 N.D. 163, 250 N.W. 787 (1933); Colwell v. Union Central Life Ins. Co. of Cincinnati, 59 N.D. 768, 232 N.W. 10, 88 A.L.R. 409 (1930); Powell v. International Harvester Co. of America, 41 N.D. 220, 170 N.W. 559 (1918).

This court has had occasion to consider the question when a party is an "adverse party" within the purview of the statute and therefore must be served with the notice of appeal. In Oil Investment Co., Inc., v. Dallea Petroleum Corp., 150 N.W.2d 189 (N.D. 1967), the third-party defendants were held not to be adverse parties and failure to serve notice upon them did not constitute a fatal jurisdictional defect. The corporate assignee of a note sued the corporate maker and two individual makers without joining three other individual makers who were stockholders of the corporate assignee.