Opinion for the Court filed by Circuit Judge SILBERMAN.
Petitioner, a bankrupt carrier, challenges the Interstate Commerce Commission’s (ICC’s) order declaring that the carrier’s rates were never effectively on file with the Commission. We agree with petitioner that the Commission’s ruling conflicts with Supreme Court precedent, and therefore, we grant the petition for review.
I.
In the early 1980s, the federal government began to deregulate the transportation industry. As part of that process, the ICC relaxed many of its cumbersome rate filing and approval procedures with which motor carriers had to comply. Even the new, less stringent, requirements were too burdensome for many carriers who, caught up in the spirit of competition, negotiated rates with shippers without regard to the rates on file with the Commission. ' In many cases, these negotiated rates were far below the carriers’ filed rates.
The shippers gladly accepted these low rates. Most of the shippers must have known that under the filed rate doctrine (which is an integral part of the Interstate Commerce Act (ICA),
see
49 U.S.C. § 10761(a), and has been consistently followed by the Supreme Court since at least 1915) the carriers had a legal right to collect the full amount of the filed rate no matter how clearly a shipping contract reflected a lower rate.
See Louisville & Nashville R. Co. v. Maxwell,
By the mid-1980s, a number of trustees had billed shippers for the difference between the filed and negotiated rates and, upon the shippers’ refusal to pay, had brought undercharge suits. The shippers understandably characterized these suits as grossly inequitable and argued that the Commission should invalidate the filed rates pursuant to its power to regulate unreasonable practices. The Commission, realizing that the undercharge suits resulted from and were contrary to the spirit of its deregula-tory efforts, agreed with the shippers.
See National Indus. Transp. League,
3 I.C.C.2d
*358
99, 104-08 (1986)
(Negotiated Rates I); Petition to Institute Rulemaking on Negotiated Motor Common Carrier Rates,
The Supreme Court, however, when it faced the issue in
Maislin Industries, U.S., Inc. v. Primary Steel, Inc.,
After their blanket challenge to the trustees’ undercharge suits was rejected in Mais-lin, shippers had to develop more creative defenses that were designed to avoid running afoul of the filed rate doctrine. This case involves one such attempt.
The trustees of the bankrupt Overland Express sued a number of shippers for undercharges in the Southern District of Indiana. A group of these shippers then filed a petition with the ICC for an order declaring Overland’s filed rates invalid. The shippers initiated this petition with the ICC rather than waiting for the district court to refer the cases to the Commission. The court eventually did refer some of the cases, but they were never consolidated with the original petition for declaratory relief. 1
The shippers’ major contention before the Commission was that Overland’s tariff referred to a separately filed mileage guide in which Overland had failed to participate, and that therefore its filed rates were defective and void as a matter of law. Understanding the shippers’ claim requires a brief overview of the Commission’s tariff filing regulations. A mileage rate is one of the methods that a carrier can use to charge shippers. It consists of two parts: a rate per mile and a distance between shipping points. A carrier will usually list the rate per mile in its filed tariff and can supply the distances by including a list of mileage figures in the same tariff, by attaching a map to that tariff, or by referring to a separately filed mileage guide compiled by a third party. See 49 C.F.R. § 1312.30(c) (1991). If a carrier chooses the third option, the ICC interprets its regulations as obligating the carrier to participate formally in the mileage guides that it incorporates by reference. See 49 C.F.R. § 1312.-27(e); Jasper Wyman & Son, et al. — Peti tion for Declaratory Order — Certain Rates and Practices of Overland Express, Inc., 8 1.C.C.2d 246, 251-52 (1992). 2 Formal participation means only that the carrier must pay a nominal fee to the publisher of the mileage guide and have a valid power of attorney on file with the publisher. See 49 C.F.R. §§ 1312.10(b), 1312.4(d). The power of attorney allows the publisher to act as the carrier’s agent when it files the mileage guide with the Commission.
Overland’s tariff referred to Mileage Guide Tariff HGB 100, published by the Household Goods Carriers’ Bureau. Athough Overland provided the Bureau with a power of attorney in 1970, the shippers claimed that it lapsed in 1983 when Overland failed to pay
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its nominal participation fee, and the publisher omitted Overland from the list of participating carriers. The shippers contended that the failure to maintain a
valid
power of attorney rendered Overland’s filed rates void, and that therefore those tariffs could not serve as the basis for an undercharge suit. Overland’s apparent oversight was not -unusual. As many as 40% of all carriers failed to satisfy the formal participation requirements for their mileage guides, and shippers have challenged this practice in a number of proceedings. Recognizing the industry-wide importance of the issue, the Commission gave notice in the Federal Register soliciting comments from interested parties.
See
56 Fed.Reg. 24,091 (1991). After reviewing the public comments and the pleadings concerning Overland in particular, the Commission decided in favor of the shippers. The Commission held that Overland, because its power of attorney had lapsed, failed to participate formally in the mileage guide.
See Jasper Wyman,
II.
Although Overland raises a number of claims, its principle contention is that the Commission’s interpretation of 49 C.F.R. § 1312.4(d) resulted in an impermissible retroactive rejection of its tariff.
3
In
ICC v. American Trucking Associations,
The Commission believes that
American Trucking
is inapposite. Its regulation provides that “[ajbsent effective concurrences or powers of attorney, tariffs are void as a matter of law.” 49 C.F.R.' § 1312.4(d). The Commission explains that if a tariff is void as a matter of law, it never became effective, and because
American Trucking
only limits the Commission’s ability to reject
effective
tariffs, it has no need to demonstrate that its remedy directly selves a specific statutory mandate.
Accord Atlantis Express, Inc. v. Associated Wholesale Grocers,
A careful reading of
American Trucking,
however, reveals that the Commission cannot
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slip the limitation on its power to reject tariffs retroactively merely by claiming that its regulation never allowed a filed tariff to take effect. Although the Court did refer to limitations on the Commission’s power to reject “effective tariffs,” it used the phrase “effective tariff’ simply to differentiate between the Commission’s express statutory authority to reject tariffs prospectively during the application process
(ie.,
before their
effective
dates), and the limited implicit authority to reject tariffs retroactively once they had gone into effect.
See American Trucking,
The Commission argues alternatively that if its remedy properly is considered a retroactive tariff rejection, it still satisfies the two-part test of
American Trucking.
The Commission suggests that when a defect is apparent on the face of the tariffs filed with the Commission, its rule is a straightforward application of the filed rate doctrine incorporated in 49 U.S.C. § 10761(a).
See Freightcor Services, Inc. v. Vitro Packaging, Inc.,
Although acknowledging that most shippers would not have noticed that the mileage guide was valid only for participating carriers, the Commission and intervenors remind us that the filed rate doctrine is an inflexible rule. And just as the filed rate doctrine helped the carriers in Maislin, here it shields shippers from undercharge suits — what is sauce for the goose is sauce for the gander. See Jasper Wyman, 8 I.C.C.2d at 257. The Commission thus interprets the filed rate doctrine in this proceeding as holding earners responsible for any errors contained in the tariffs filed before the Commission. As long as a shipper can point to a procedural defect evident in the filed tariffs, the rate incorporated in the tariff does not apply.
The Commission’s approach, although it may satisfy “poetic justice,” does not meet the more straightforward demands of law; it turns the filed rate doctrine on its head. The Supreme Court has long held that a filed rate is valid despite procedural imperfections and even if it reflects a substantive violation of
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the ICA.
See Davis v. Portland Seed Co.,
This rigid approach was deemed necessary to prevent carriers from intentionally “misquoting” rates to shippers as a means of offering them rebates or discounts. As the Commission itself found: “[P]ast experience shows that billing clerks and other agents of carriers might easily become experts in the making of errors and mistakes in the quotation of rates to favored shippers, while other shippers, less fortunate in their relations with carriers and whose traffic is less important, would be compelled to pay the higher published rates.”
Maislin,
The Court’s strict enforcement of the filed rate doctrine is, then, an unyielding insistence that the rate on file is the lawful rate. The carriers and the shippers are bound by that which is openly disclosed so as to prevent price discrimination. That purpose is hardly served, indeed it is undermined, by an ICC policy that would make the disclosed rate unreliable unless a shipper took the extraordinary step of determining whether a carrier’s tariff filing was defective because its power of attorney was not up to date. 6 The section of the Act on which the filed rate doctrine is based, 49 U.S.C. § 10761(a), does not make every defect in the filed tariff absolutely disqualifying. Rather, it provides that a “carrier may not charge or receive a different compensation for that transportation or service than the rate specified in the tariff.” 49 U.S.C. § 10761(a) (emphasis added). (It is perhaps for this reason that there is a filed rate doctrine rather than a filed tariff doctrine.)
As long as the tariff documents “were received and placed on file by the Commission without any objection whatever as to their form and ... were adequate to give notice” of the rate to be charged, the filed rate doctrine applies.
Berwind-White Coal Mining Co. v. Chicago & Erie R.R.,
The Commission does offer other statutory justifications for its rule. It points out that the Fifth Circuit has suggested that the rule furthers the specific statutory mandate that “[t]he Commission may prescribe other information that motor common carriers shall include ■ in their tariffs.” 49 U.S.C. § 10762(a)(1);
see Freightcor,
We rather doubt that § 10762(a)(l)’s permissive authorization for the Commission to require carriers to include other unspecified information is the type of “specific statutory mandate” the Court had in mind in
American Trucking.
And the Commission does not seem authorized to reject tariffs retroactively to satisfy a
regulatory
policy not driven by a specific statutory mandate. Be that as it may, even if ensuring that carriers have valid powers of attorney on file (and guaranteeing that the mileage guide publishers are paid their membership fees) is a permissible statutory goal, the draconian remedy of retroactive rejection does not seem directly and closely tied to that policy. In approving the retroactive rejection remedy in
American Trucking,
the Court emphasized that other less drastic remedies, like actual damages, were ineffective.
American Trucking,
Finally,
American Trucking
also stressed the procedural protections that the Commission employed to avoid inequitable results in that context. The Court noted first that tariffs would be rejected only “upon findings of substantial violations.”
American Trucking,
The Commission’s declaratory order constitutes a retroactive tariff rejection in excess of its statutory authority and violates the filed rate doctrine. The petition for review is therefore granted.
Notes
. The Commission suggests that jurisdiction properly lies in the Southern District of Indiana under 28 U.S.C. § 1336(b), which gives a district court exclusive jurisdiction over cases that it previously referred to the Commission. But § 1336(b) is a narrow exception to our jurisdiction over challenges to Commission proceedings under the Hobbs Act. See 28 U.S.C. §§ 2321(a), 2342. We have jurisdiction over this proceeding because it was initiated by the shippers (some of whom never had their cases referred to the Commission), not referred by a district court, and was later supplemented by notice and comment proceedings.
. Although Overland challenges this interpretation, we need not consider the validity of the Commission's construction because of our disposition of Overland's other arguments.
. The Commission suggests that petitioner's attack on the validity of 49 C.F.R. § 1312.4(d), promulgated in 1984, violates the Hobbs Act's 60-day limitation on challenges to agency regulations.
See
28 U.S.C. § 2344. But we generally allow claims, like petitioner's, that a regulation is in excess of statutory authority when raised as a defense to an agency enforcement action.
See NLRB Union v. FLRA,
. The Commission’s ability to reject tariffs retroactively only became an issue after 1979 when staff and budget cuts forced the Commission to abandon its policy of scrutinizing every tariff filing.
See American Trucking,
. Attempting to distinguish
Portland Seed
and other decisions that refused to hold tariffs void despite defects,
see American Trucking,
. The filed rate doctrine and
American Trucking’s
general prohibition on retroactive tariff rejections are
interrelated
— American
Trucking
limits the Commission's authority to disturb the filed rate.
See American Trucking,
