an agency and an outside party. All of the information as to what the Air Force offered West Publishing, initially and in response to West’s counter-offers, has already .been fully disclosed to at least one party outside the Department — West itself — and the Department has no control over further disclosure.
Perhaps it could be shown that the threat of disclosure of negotiation proceedings would so inhibit private parties from dealing with the Government that agencies must be permitted to withhold such information in order to preserve their ability to effectively arrange for contractual agreements. Cf. Brockway, supra, 518 F.2d at 1193; Machin v. Zuckert, 114 U.S.App.D.C. 335, 316 F.2d 336, cert. denied, 375 U.S. 896, 84 S.Ct. 172, 11 L.Ed.2d 124 (1963). Argu ments that the disclosure mandated by the FOIA would seriously hamper the performance of an agency’s other duties have not fared well in the courts, however.44 An agency cannot meet its statutory burden of justification by conclusory allegations of possible harm. It must show by specific and detailed proof that disclosure would defeat, rather than further, the purposes of the FOIA. See Brockway, supra, 518 F.2d at 1194.
Whatever might be shown with respect to the harm caused by disclosure of the offers and counter-offers made during negotiation of a government contract, the justification claimed by the Air Force in this case is far from, sufficient. Unless far more compelling reasons are brought forth on remand and supported by adequately detailed proof, the district court will have no option but to compel disclosure of document 3.
IV. AIR FORCE REGULATIONS
Since the exemptions to the FOIA are permissive rather than mandatory, particularly with respect to information that does not raise issues of individual privacy rights, an agency may impose upon itself a more liberal disclosure rule than that required by the FOIA.45 The Air Force has done just that by providing by regulation that even though a requested document or portion thereof falls within an exemption, it should nonetheless be disclosed “unless it is also determined that a significant and legitimate Government purpose would be served by exercising the exemption.” 32 C.F.R. § 806.23 (1976). In view of the well-established principle that an agency is bound by its own regulations,46 we must determine whether the Air Force has demonstrated such a purpose for withholding the documents at issue in this case.47
In both its initial reply to Mead Data’s request and notification of the result of Mead Data’s administrative appeal, the Air Force indicated that it would not disclose the information requested because to do so “would inhibit Air Force personnel from expressing their candid opinions in the future,” J. A. at 8, “and adversely affect the decisional process within the Air Force.” Id. at 10. In his affidavit, filed in the district court, the Chief of the Air Force’s General Litigation Division reiterated that he had denied disclosure because it “would
44
See Hawkes v. IRS, 507 F.2d 481, 484 (6th Cir. 1974).
45
See Westinghouse Elec. Corp. v. Schlesinger, 542 F.2d 1190, 1197 (4th Cir. 1976), cert.
denied, 431 U.S. 924, 97 S.Ct. 2199, 53 L.Ed.2d 239 (1977);
Charles River Park “A”, Inc. v.
Department of HUD, 171 U.S.App.D.C. 286, 292, 519 F.2d 935, 941 (1975);
Moore-McCor-mack, Inc. v. I.T.O. Corp., supra, 508 F.2d at 950; S.Rep.No.93-854, 93d Cong., 2d Sess. 6 (1974); K. Davis, Administrative Law Treatise § 3A.5 (Supp.1970); Note,
Developments Under the Freedom of Information Act — 1974, 1975 Duke L.J. 416, 430-31.
46
Morton v. Ruiz, 415 U.S. 199, 235, 94 S.Ct. 1055, 39 L.Ed.2d 270 (1974); Service v. Dulles, 354 U.S. 363, 77 S.Ct. 1152, 1 L.Ed.2d 1403 (1957); GSA v. Benson, 415 F.2d 878, 880 (9th Cir. 1969).
47
We also bear in mind the principle that an agency’s interpretation of its own rule is entitled to a presumption of validity. See K. Davis, Administrative Law Treatise § 30.12 (1958);
cf. Griggs v. Duke Power Co., 401 U.S. 424, 433-34, 91 S.Ct. 849, 28 L.Ed.2d 158 (1971);
Contractors Ass’n v.
Secretary of Labor, 442 F.2d 159, 175 (3d Cir.),
cert. denied, 404 U.S. 854, 92 S.Ct. 98, 30 L.Ed.2d 95 (1971).