Oklahoma Gas and Electric Company v. FERC ( 2021 )


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  •  United States Court of Appeals
    FOR THE DISTRICT OF COLUMBIA CIRCUIT
    Argued April 14, 2021               Decided August 27, 2021
    No. 20-1062
    OKLAHOMA GAS AND ELECTRIC COMPANY,
    PETITIONER
    v.
    FEDERAL ENERGY REGULATORY COMMISSION,
    RESPONDENT
    CPV KEENAN II RENEWABLE ENERGY COMPANY, LLC, ET AL.,
    INTERVENORS
    Consolidated with 20-1101
    On Petitions for Review of Orders
    of the Federal Energy Regulatory Commission
    John Longstreth and Matthew J. Binette argued the causes
    for petitioners Oklahoma Gas and Electric Company and
    Southwest Power Pool, Inc. With them on the joint briefs were
    Donald A. Kaplan and Victoria M. Lauterbach.
    Bruce A. Grabow, Jennifer Brough, Stuart A. Caplan,
    Matthew A. Fitzgerald, Noel Symons, Daniel E. Frank, Allison
    2
    E. Speaker, and Molly Suda were on the joint briefs for
    intervenors CPV Keenan II Renewable Energy Company,
    LLC, et al. in support of petitioners. William M. Keyser,
    entered an appearance.
    Beth G. Pacella, Deputy Solicitor, Federal Energy
    Regulatory Commission, argued the cause for respondent.
    With her on the brief were David L. Morenoff, Acting General
    Counsel, and Robert H. Solomon, Solicitor.
    Joseph W. Lowell argued the cause for intervenors Xcel
    Energy Services Inc., et al. in support of respondent. With him
    on the joint brief were Craig W. Silverstein, Stephen C.
    Pearson, Cynthia S. Bogorad, Amanda C. Drennen, Stacey L.
    Burbure, Phyllis G. Kimmel, Stephen M. Spina, and Timothy T.
    Mastrogiacomo.
    Before: TATEL, RAO, and WALKER, Circuit Judges.
    Opinion for the Court filed by Circuit Judge RAO.
    RAO, Circuit Judge: This case concerns the authority of
    the Federal Energy Regulatory Commission (“FERC” or
    “Commission”) to order a retroactive waiver of a billing
    requirement contained in a filed tariff. Several utilities that are
    managed by the Southwest Power Pool (“SPP”), a regional
    transmission operator, paid for upgrades to the transmission
    grid. The operative tariff required other utilities who benefitted
    from these upgrades to share the costs of the expanded
    network. The tariff, however, also required SPP to invoice the
    charges monthly and to make any adjustments within one year.
    The reimbursement calculation proved complicated, and it took
    SPP eight years to implement it, during which time SPP did not
    invoice for the upgrade charges.
    3
    The Commission initially granted SPP a waiver of the
    tariff’s one-year time bar, but later determined it lacked the
    authority to waive this provision retroactively. FERC’s revised
    determination meant the utilities that had made substantial
    outlays for upgrades were denied reimbursement for the eight
    years that had elapsed. SPP and Oklahoma Gas and Electric,
    one of the companies that sponsored upgrades and has been
    denied reimbursement, filed these consolidated petitions for
    review.
    We deny the petitions. Once a tariff is filed, the
    Commission has no statutory authority to provide equitable
    exceptions or retroactive modifications to the tariff. SPP may
    impose only those charges contained in the filed rate. Because
    the one-year time bar for billing is part of the filed rate, FERC
    could not retroactively waive it, even to remedy the arguable
    windfall for users of the upgraded transmission networks.
    FERC therefore properly denied the waiver, and it was not
    arbitrary or capricious to order SPP to refund the retroactive
    charges it had collected under the invalidated waiver.
    I.
    SPP is a regional transmission organization servicing
    about 60,000 miles of transmission lines stretching from
    Arkansas to Wyoming and from Texas to North Dakota. SPP
    manages the transmission of electricity by collecting and
    distributing various charges and revenues among its
    stakeholders, which include both private and public utilities.
    SPP and its stakeholders operate under a tariff approved by
    FERC.
    When a utility seeks to expand its generation capabilities,
    it may need transmission service beyond what the transmission
    grid currently can accommodate. To facilitate and encourage
    4
    investment in upgrades to the grid, SPP proposed a
    reimbursement mechanism to its tariff, which FERC accepted.
    See Sw. Power Pool, Inc., 
    110 FERC ¶ 61,028
     (2005).
    Attachment Z provided that a utility would initially fund
    upgrades needed to accommodate its expansion of service—
    that utility is the “upgrade sponsor.” Other utilities that
    subsequently use the upgraded transmission facilities—the
    “upgrade users”—would pay a share of the upgrade costs. This
    reimbursement would continue until the upgrade sponsor was
    fully reimbursed. SPP later proposed, and FERC accepted,
    Attachment Z2, which clarified the standard for imposing
    upgrade charges. See Sw. Power Pool, Inc., 
    123 FERC ¶ 61,208
    (2008). Under Attachment Z2, an upgrade sponsor would
    receive credits from any upgrade users whose service could not
    be provided “but for” the upgrade. See Resp’t Br. Add. 10–16
    (Attachment Z2).
    Later that year, Oklahoma Gas and Electric Company
    (“Oklahoma Gas”), an SPP stakeholder, wanted to develop
    wind generation in western Oklahoma. Although this region
    has strong winds, it lacked sufficient connection to the
    transmission grid to profitably move the energy to market.
    Oklahoma Gas decided to fund upgrades to the grid’s
    transmission facilities in reliance on Attachment Z2’s promise
    of credits from later users of the upgrades.
    Meanwhile, the implementation of the upgrade crediting
    process proved to be complex. SPP obtained a vendor to
    develop special software necessary to calculate the upgrade
    charges, but it encountered delays and problems over the next
    several years. In the meantime, sponsors continued to fund
    network upgrades. SPP utilized a task force composed of its
    stakeholders to address the calculation of the upgrade charges.
    This stakeholder process kept the relevant parties apprised of
    SPP’s efforts to implement the upgrade charges. SPP also
    5
    periodically provided “study reports” to the utilities, which
    contained notations that upgrade charges “may be required for
    the following Network Upgrades in accordance with
    Attachment Z2.” J.A. 89. In 2015, SPP found a new software
    vendor and a year later, finally was able to calculate the
    upgrade charges for 2008 to 2016, which the parties refer to as
    the “historical period.” At this point, the utilities using the
    upgrades had not been billed for their share of the upgrade
    costs.
    By 2016, Oklahoma Gas had completed the upgrades to
    transmit the energy it generated from wind. Several other SPP
    stakeholders, including Xcel Energy Services, also used these
    transmission upgrades. Although Oklahoma Gas was entitled
    to compensation, it had not received any credits for its upgrade
    costs.
    Out of what it said was an abundance of caution, SPP
    petitioned FERC for a waiver of a tariff provision governing
    the timing of invoices. Section I.7.1 of SPP’s tariff provides
    that, “[w]ithin a reasonable time after the first day of each
    month, [SPP] shall submit an invoice to the Transmission
    Customer for the charges for all services furnished under the
    Tariff during the preceding month.” Pet’rs Br. Add. 15
    (hereinafter Tariff § I.7.1). Although SPP may later adjust the
    bills, adjustments must be made “within one year after
    rendition of the bill reflecting the actual data for such service.”
    Tariff § I.7.1. SPP sought a waiver of Section I.7.1 to permit it
    to bill upgrade users for the upgrade charges incurred during
    the historical period, i.e., more than a year prior. Xcel, along
    with several other upgrade users, objected to the waiver request
    on the ground that Section I.7.1 is part of the filed rate, so the
    Commission cannot waive it.
    6
    The Commission initially granted SPP a waiver of
    Section I.7.1, applying the waiver both retroactively and
    prospectively. See Sw. Power Pool, Inc., 
    156 FERC ¶ 61,020
    ,
    slip decision (2016). Citing its four-part test for a waiver,
    FERC found that (1) SPP acted in good faith; (2) it sought a
    waiver of limited scope; (3) the waiver addressed a concrete
    problem; and (4) the waiver had no undesirable consequences.
    See 
    id.,
     slip decision at 21 ¶ 52. FERC denied the upgrade
    users’ request for rehearing. See Sw. Power Pool, Inc., 
    161 FERC ¶ 61,144
     (2017). With the waiver in hand, SPP began to
    collect upgrade charges from the upgrade users for the
    historical period. SPP then distributed about $140 million in
    revenue credits to upgrade sponsors.
    Xcel petitioned this court for review of the waiver orders.
    Before briefing was complete, we issued a decision in Old
    Dominion Electric Cooperative v. FERC, which reinforced that
    FERC has “no discretion to waive the operation of a filed rate
    or to retroactively change or adjust a rate for good cause or for
    any other equitable considerations.” 
    892 F.3d 1223
    , 1230 (D.C.
    Cir. 2018). We then granted FERC’s unopposed motion to
    remand so that FERC could consider the application of Old
    Dominion to this case in the first instance.
    On remand, the Commission reversed course and denied
    the retroactive waiver of the one-year billing requirement in
    Section I.7.1. See Sw. Power Pool, Inc., 
    166 FERC ¶ 61,160
    ,
    slip decision (2019). FERC found that Section I.7.1’s billing
    requirements are part of SPP’s filed rate, and a waiver would
    impermissibly allow for retroactive billing of upgrade users in
    contravention of the filed rate. The Commission rejected SPP’s
    argument that it had provided upgrade users with notice
    sufficient to satisfy the filed rate doctrine. The Commission
    also ordered SPP to refund the upgrade charges it had already
    collected from the upgrade users for the historical period. Two
    7
    commissioners filed concurring opinions to highlight the
    inequity of this situation, though they agreed that the
    Commission correctly denied the waiver and ordered the
    refund. These commissioners emphasized that SPP’s failure to
    implement Attachment Z2 for eight years meant that sponsors
    of transmission upgrades, like Oklahoma Gas, had been
    deprived of revenue and the users of those upgrades had
    received a windfall. FERC denied rehearing. See Sw. Power
    Pool, Inc., 
    170 FERC ¶ 61,125
    , slip decision (2020).
    This court has jurisdiction to review SPP’s and Oklahoma
    Gas’s (“petitioners”) consolidated petitions under 16 U.S.C.
    § 825l(b). We review FERC’s orders to determine whether they
    are “arbitrary, capricious, an abuse of discretion, or otherwise
    not in accordance with law.” 
    5 U.S.C. § 706
    (2)(A).
    II.
    The Commission concluded that the one-year billing
    requirement in Section I.7.1 applied to the upgrade charges and
    was part of the filed rate that could not be waived retroactively.
    The petitioners argue first that the tariff did not prohibit SPP
    from billing upgrade users more than one year after the upgrade
    charges accrued. Second, the petitioners maintain that, even if
    the time limit applied, FERC could provide a waiver because
    the utilities using the upgrades were on notice that they would
    be charged once the calculations were made. We take each
    argument in turn.
    A.
    When reviewing the Commission’s interpretation of a
    tariff, this court first “consider[s] de novo whether the relevant
    language unambiguously addresses the matter at issue,” and if
    so, we apply that unambiguous meaning. NextEra Desert Ctr.
    8
    Blythe, LLC v. FERC, 
    852 F.3d 1118
    , 1121 (D.C. Cir. 2017)
    (cleaned up). “If, however, there is ambiguity, we defer to the
    Commission’s construction so long as that construction is
    reasonable.” 
    Id.
     (cleaned up). We find the tariff provisions at
    issue unambiguously apply to the upgrade charges.
    A tariff provision must be understood according to its plain
    meaning, which we draw from its text and context. Cf. Ameren
    Servs. Co. v. FERC, 
    330 F.3d 494
    , 499 (D.C. Cir. 2003).
    Section I.7.1 provides:
    Within a reasonable time after the first day of
    each month, [SPP] shall submit an invoice to
    the Transmission Customer for the charges for
    all services furnished under the Tariff during
    the preceding month.… Invoices may be issued
    using estimated data, to the extent actual data is
    not available by the fifth (5th) working day of
    the month following service. Adjustments
    reflecting the difference in billing between the
    estimated and actual data will be included on the
    next regular invoice, with such adjustment
    being due when that invoice is due. Any other
    corrections found to be necessary will be made
    on the next regular monthly invoice.
    Bills will be adjusted to correct for all provable
    meter errors. Billing adjustments for reasons
    other than (a) the replacement of estimated data
    with actual data for service provided, or (b)
    provable meter error, shall be limited to those
    corrections and adjustments found to be
    appropriate for such service within one year
    9
    after rendition of the bill reflecting the actual
    data for such service.
    Tariff § I.7.1 (emphases added).
    Section I.7.1 unambiguously requires SPP to provide a
    monthly invoice to its stakeholders for all charges incurred
    during the preceding month. As the petitioners conceded,
    upgrade charges are “charges for [a] service[] furnished under
    the Tariff.” Tariff § I.7.1; see also Oral Arg. Tr. 14:18–22,
    22:12–16. SPP was thus obligated to bill for them monthly.
    Attachment Z2, which sets out the arrangement for sharing
    upgrade costs, is not to the contrary. This provision was an
    addition to the tariff that included Section I.7.1, but the addition
    included no language overriding Section I.7.1’s billing
    requirements. In fact, Attachment Z2 says nothing at all about
    the timing of billing for upgrade charges. Based on the plain
    language of the tariff, we agree with the Commission that
    Section I.7.1 applied to the upgrade charges during the
    historical period.
    The petitioners provide several reasons why Section I.7.1
    does not apply to the upgrade charges. They first argue that
    Section I.7.1 has no application because that provision
    concerns billing “adjustments,” whereas the upgrade charges
    concern the initial settlement of those charges. To be sure, the
    second paragraph of Section I.7.1 focuses on billing
    adjustments, generally prohibiting them one year after the
    initial bill. Yet the petitioners ignore the first paragraph’s
    requirement that SPP bill for all charges on a monthly basis,
    which SPP failed to do for the upgrade charges. That SPP did
    not calculate the upgrade charges until recently does not excuse
    its failure to comply with Section I.7.1’s monthly billing
    requirement. As the Commission explained, Section I.7.1
    10
    contains “no exception for processes or services that may take
    longer than one year to implement.” 
    170 FERC ¶ 61,125
    , slip
    decision at 11 ¶ 24. Moreover, it would permit an end run
    around the monthly billing requirement and the one-year
    prohibition on adjustments if SPP could avoid both those
    obligations by never providing an initial bill.1
    Next, the petitioners rely on Section I.7.1’s provisions
    regarding the use of estimated data until actual data is
    available. They reason that Section I.7.1 did not apply until the
    actual data could be calculated, so no monthly bill was required
    while the necessary software was being developed. The
    petitioners cannot benefit from this provision for a simple
    reason: SPP never provided estimated data on the upgrade
    charges. The first paragraph of Section I.7.1 provides that SPP
    may use estimated data on the monthly invoice “to the extent
    actual data is not available by the fifth (5th) working day of the
    month following service.” Tariff § I.7.1. The petitioners
    suggest the study reports may be used as the relevant
    “estimated data,” but the notations in those reports indicate
    only that “[c]redits may be required for the following Network
    Upgrades in accordance with Attachment Z2.” See, e.g.,
    J.A. 89. This general reference to upgrade charges hardly
    constitutes estimated data for those charges, much less
    estimated charges provided on a monthly invoice. Because SPP
    1
    The petitioners also argue that SPP satisfied Section I.7.1 by
    providing a bill for the upgrade charges within a “reasonable time.”
    This overlooks that Section I.7.1 requires SPP to bill its stakeholders
    “[w]ithin a reasonable time after the first day of each month.” Tariff
    § I.7.1. In context, the amount of “reasonable time” is cabined by a
    monthly limitation. SPP’s billing for upgrade charges years after they
    were incurred is plainly not “a reasonable time after the first day of
    each month.” Tariff § I.7.1.
    11
    never provided estimated data, it cannot now bill for the actual
    charges beyond the one-year limitation period.2
    The petitioners also maintain that FERC’s interpretation
    fails to give effect to Attachment Z2. Whenever possible, the
    provisions of a tariff should be interpreted harmoniously “so as
    to give effect to all of its provisions and to avoid rendering any
    provision meaningless.” Pub. Serv. Co. of N.H. v. N.H. Elec.
    Coop., 
    86 FERC ¶ 61,174
    , 61,598 (1999). Under petitioners’
    interpretation, however, SPP can collect the upgrade charges
    set forth in Attachment Z2 regardless of the billing
    requirements of Section I.7.1. By contrast, the Commission’s
    interpretation gives effect to both tariff provisions, allowing
    SPP to collect the upgrade charges set forth in Attachment Z2,
    but only by following the billing requirements of Section I.7.1.
    The petitioners finally suggest that FERC incorrectly
    elevated the “non-rate” terms about billing over the rates
    specified in Attachment Z2. Because utilities relied on that rate
    when sponsoring transmission upgrades, the rate should be
    implemented with retroactive billing, irrespective of the timing
    requirements in Section I.7.1. The Commission reasonably
    concluded, however, that rate certainty cut the other way
    because the enforcement of Section I.7.1’s requirements
    “assures customers that a utility cannot assess them new
    2
    The petitioners contend that FERC confused estimated charges with
    estimated data, the latter of which is all that Section I.7.1 requires.
    We disagree. Although Section I.7.1 provides that “[i]nvoices may
    be issued using estimated data,” those invoices must include “the
    charges for all services furnished” that month. Tariff § I.7.1.
    Accordingly, estimated data may be used to calculate the charges on
    the monthly invoices, but estimated charges based on that data are
    still required on the invoices. Regardless, SPP provided neither
    estimated data nor estimated charges to the upgrade users.
    12
    charges after the one-year timeframe for doing so lapses.” 
    170 FERC ¶ 61,125
    , slip decision at 12 ¶ 25.
    A plain reading of Section I.7.1 establishes that SPP could
    not bill for upgrade charges more than one year after the
    charges were incurred by the upgrade users.
    B.
    Because Section I.7.1’s billing requirements applied to the
    upgrade charges, SPP needed a waiver from FERC to impose
    those charges retroactively. FERC denied the waiver,
    concluding a waiver would effectively result in a retroactive
    change in the rates and therefore run afoul of the filed rate.
    FERC’s decision was reasonable and consistent with this
    court’s articulation of the filed rate doctrine and the statutory
    limits on FERC’s authority to modify rates retroactively.
    The Commission must ensure regulated entities charge
    “just and reasonable” rates. 16 U.S.C. § 824d(a). As
    incorporated into the Federal Power Act, regulated entities are
    required to file with FERC “schedules showing all rates and
    charges … and the classifications, practices, and regulations
    affecting such rates and charges.” Public Utility Holding
    Company Act of 1935, ch. 687, § 205, 
    49 Stat. 838
    , 851
    (codified as amended at 16 U.S.C. § 824d(c)). Once filed, “no
    change shall be made … in any such rate, charge,
    classification, or service, or in any rule, regulation, or contract
    relating thereto, except after sixty days’ notice to the
    Commission and to the public” in another filing with FERC. 16
    U.S.C. § 824d(d). As the statutory terms make clear, the filed
    rate “is not limited to ‘rates’ per se,” but also extends to matters
    “directly affect[ing] … rates.” Nantahala Power & Light Co.
    v. Thornburg, 
    476 U.S. 953
    , 966–67 (1986). It follows that
    13
    FERC “has no authority under the Act to allow retroactive
    change in the [filed] rates.” Old Dominion, 892 F.3d at 1226.
    These statutory provisions “mandating the open and
    transparent filing of rates and broadly proscribing their
    retroactive adjustment are known collectively as the ‘filed rate
    doctrine.’” Id. at 1226–27; see also Towns of Concord v.
    FERC, 
    955 F.2d 67
    , 70–72 (D.C. Cir. 1992) (detailing the
    origins of the filed rate doctrine and its justifications). The so-
    called “doctrine” is shorthand for the interconnected statutory
    requirements that bind regulated entities to charge only the
    rates filed with FERC and to change their rates only
    prospectively. When it applies, the filed rate doctrine is “a
    nearly impenetrable shield” and does not yield, “no matter how
    compelling the equities.” Old Dominion, 892 F.3d at 1230.
    In this case, SPP failed to comply with Section I.7.1’s
    billing requirements for the upgrade charges, and it now seeks
    a retroactive waiver of those requirements, particularly its one-
    year prohibition on billing adjustments. As FERC found,
    however, Section I.7.1 is part of the filed rate. See 
    166 FERC ¶ 61,160
    , slip decision at 27 ¶ 50. If the Commission waived
    Section I.7.1’s time bar, SPP would be permitted to charge
    something other than the filed rate. Accordingly, the
    Commission did not act arbitrarily or capriciously when it
    denied SPP a retroactive waiver of Section I.7.1.
    The petitioners do not contest Section I.7.1 is part of the
    filed rate. They instead reiterate that FERC should not elevate
    a “non-rate” term like Section I.7.1, which governs the timing
    of invoices, over a rate term like Attachment Z2, which directly
    imposes charges. The filed rate requirements are not so
    confined. See Nantahala Power & Light, 
    476 U.S. at
    966–67.
    The Federal Power Act prohibits changes, not just to a rate, but
    also to “any such rate, charge, classification, or service, or in
    14
    any rule, regulation, or contract relating thereto.” 16 U.S.C.
    § 824d(d).
    Non-rate terms within the tariff may not be changed
    retroactively, and those include billing limitations.3 For
    example, the First Circuit has held that a tariff provision that
    “mak[es] charges incontestable if not challenged within one
    year” is “part and parcel of the rate schedule for purposes of
    the filed rate doctrine.” Boston Edison Co. v. FERC, 
    856 F.2d 361
    , 368, 371 (1st Cir. 1988). FERC has likewise found that
    billing limitations are part of the filed rate. See Seminole Elec.
    Coop., Inc. v. Fla. Power & Light Co., 
    139 FERC ¶ 61,254
    ,
    62,873 (2012) (finding “the 24-month limitation on retroactive
    billing in [the tariff] is itself the filed rate”); N.Y. Indep. Sys.
    Operator, Inc., 
    128 FERC ¶ 61,086
    , 61,464 (2009) (finding a
    tariff provision prohibiting corrections to finalized invoices is
    part of the filed rate). In this case, Section I.7.1’s billing
    requirements, although non-rate terms, are part of the filed rate.
    The statute provides no grounds for distinguishing rate and
    non-rate terms, but rather binds parties to the terms in the filed
    tariff.
    The petitioners next suggest they should benefit from an
    “exception” to the filed rate doctrine because SPP gave notice
    to the upgrade users that they would be responsible for upgrade
    3
    We note that FERC has rejected a distinction between rate and non-
    rate terms in its recent proposed guidance on waivers. See Proposed
    Policy Statement on Waiver of Tariff Requirements, 
    171 FERC ¶ 61,156
    , 62,265 (2020) (“[T]here is no basis for the Commission to
    conclude that those doctrines apply any differently to non-rate terms
    and conditions than to rates.”); accord Sunflower Elec. Power Corp.,
    
    173 FERC ¶ 61,054
    , 61,340 (2020) (Danly, dissenting) (“Any
    conclusion that a distinction can be drawn regarding the applicability
    of these doctrines to rate versus non-rate terms is questionable at
    best.”).
    15
    charges once properly calculated. “[T]he filed rate doctrine
    simply does not extend to cases in which buyers are on
    adequate notice that resolution of some specific issue may
    cause a later adjustment to the rate being collected at the time
    of service.” W. Deptford Energy, LLC v. FERC, 
    766 F.3d 10
    ,
    22 (D.C. Cir. 2014) (cleaned up).
    This purported exception, however, does not recognize
    any sort of notice given by one regulated entity to another.
    Rather, notice may satisfy the filed rate doctrine when entities
    have formal notice of the rates, as recognized by the two well-
    established circumstances in which the court has found
    adequate notice. First, the filed rate requirements are satisfied
    when a tariff has a formula for calculating a rate, which states
    clearly that charges will depend on application of the formula.
    Old Dominion, 892 F.3d at 1231–32; see also NSTAR Elec. &
    Gas Corp. v. FERC, 
    481 F.3d 794
    , 801 (D.C. Cir. 2007)
    (concluding that a FERC rule provided notice to the market
    participants). Second, the filed rate requirements are not
    violated when a court invalidates a filed rate as unlawful, and
    FERC must make retroactive changes to the rates. W. Deptford
    Energy, 766 F.3d at 22. In both instances the regulated parties
    receive formal notice—either through a FERC proceeding or
    through the courts. Understood in this light, these are not
    exceptions so much as further elaborations of the boundaries of
    the statutory requirements that comprise the filed rate doctrine.
    Accordingly, we have generally declined to find notice
    outside of these “two limited circumstances.” Old Dominion,
    892 F.3d at 1227. The petitioners argue that SPP provided
    notice of the upgrade charges in three sources: Attachment Z2,
    the stakeholder process in which some stakeholders
    participated, and the notations in SPP’s study reports. None of
    these sources provides the type of formal notice required to
    satisfy the filed rate doctrine.
    16
    First, although Attachment Z2 was an addition to the filed
    rate that set forth the possibility of upgrade charges, it did not
    provide notice that upgrade users could be charged outside of
    Section I.7.1’s billing requirements. To constitute sufficient
    notice, “the relevant audience [must be] on notice at the outset
    that the rates” are “subject to later revision.” NSTAR, 
    481 F.3d at 801
     (cleaned up). Attachment Z2 made no mention of
    overriding or changing the timing of billing in Section I.7.1,
    nor did it suggest that difficulties in calculation could result in
    charges outside the normal billing period. Cf. Old Dominion,
    892 F.3d at 1231 (concluding that a tariff provision did not
    provide sufficient notice because it failed to forewarn that
    “some specific issue may cause a later adjustment to the rate
    being collected at the time of service”) (cleaned up).
    Attachment Z2 failed to provide the requisite notice that
    upgrade charges could occur outside Section I.7.1’s billing
    requirements.
    The other two alleged sources of notice—the stakeholder
    process and SPP’s study reports—cannot provide sufficient
    notice. Whatever information they might have provided, they
    were not filed with the Commission, and a filing “is required
    for all rate changes.” Id. at 1232 (finding a website statement
    regarding possible retroactive charges insufficient because it
    was not filed with FERC).
    We recognize that SPP apprised stakeholders of ongoing
    efforts to calculate the upgrade charges and the study reports
    noted that “[c]redits may be required” for upgrades “in
    accordance with Attachment Z2”—actions that may have
    notified stakeholders that SPP intended to bill for shared
    upgrade costs in the future. J.A. 89. Nonetheless, the type of
    notice that matters for the filed rate doctrine is formal notice,
    usually notice filed with FERC. Nothing in the filed tariff
    17
    indicated that upgrade charges could be billed outside of
    Section I.7.1’s limitations.
    FERC was therefore prohibited from waiving Section I.7.1
    for the historical period at issue.4 The Commission “may not
    disinter the past merely because experience has belied
    projections, whether the advantage went to customers or the
    utility; bygones are bygones.” Associated Gas Distribs. v.
    FERC, 
    898 F.2d 809
    , 810 (D.C. Cir. 1990) (Williams, J.,
    concurring in the denial of rehearing and rehearing en banc).
    The filed rate requirement is stringent and admits of no
    equitable adjustments by the Commission or this court.
    III.
    We next consider whether FERC acted arbitrarily or
    capriciously by ordering a refund of the upgrade charges SPP
    collected under FERC’s initial, but mistaken, waiver. When
    reviewing the Commission’s exercise of its remedial powers,
    we apply the arbitrary and capricious standard, but the “scope
    of judicial review is particularly narrow.” See La. Pub. Serv.
    4
    The petitioners highlight that FERC has sometimes waived time
    bars. That is true, but the decisions they cite failed to consider the
    requirements of the filed rate doctrine. See, e.g., Sw. Power Pool,
    Inc., 
    153 FERC ¶ 61,180
     (2015). Because FERC correctly applied
    the filed rate doctrine here, prior waivers that failed to consider these
    requirements are not germane. The Commission’s proposed policy
    statement recognizes that some of its earlier decisions “drifted
    beyond the limits imposed by the filed rate doctrine and the rule
    against retroactive ratemaking,” and the Commission has proposed
    guidance to avoid such drifting in the future. See Proposed Policy
    Statement on Waiver of Tariff Requirements, 
    171 FERC ¶ 62,264
    ;
    see also 
    id. ¶ 62
    ,266 & nn.36–37.
    18
    Comm’n v. FERC, 
    772 F.3d 1297
    , 1302 (D.C. Cir. 2014)
    (cleaned up).
    The Commission may craft a variety of remedies under
    Section 309 of the Federal Power Act.5 The filed rate doctrine,
    however, limits that remedial authority. See Verso Corp. v.
    FERC, 
    898 F.3d 1
    , 10 (D.C. Cir. 2018); Pub. Utils. Comm’n of
    Cal. v. FERC, 
    988 F.2d 154
    , 168 n.12 (D.C. Cir. 1993)
    (explaining that if FERC’s actions “violated the filed rate
    doctrine or the rule against retroactive ratemaking, we would
    not then invoke the Commission’s assessment of the equities to
    overcome those violations”). Once FERC determined that its
    initial waiver of Section I.7.1 ran afoul of the filed rate, the
    natural consequence was to order a refund of charges billed for
    the historical period. FERC stated it would be “inappropriate”
    to exercise equitable authority here, because its initial waiver
    violated the filed rate doctrine. 
    166 FERC ¶ 61,160
    , slip
    decision at 30 ¶ 57. Given FERC’s broad remedial discretion,
    that decision was not arbitrary and capricious.
    The petitioners also argue that ordering the refund defies
    the cost causation principle, under which “all approved rates
    [must] reflect to some degree the costs actually caused by the
    customer who must pay them.” Midwest ISO Transmission
    Owners v. FERC, 
    373 F.3d 1361
    , 1368 (D.C. Cir. 2004)
    (cleaned up). When “a utility benefits from the costs of new
    facilities,” the cost causation principle dictates that the utility
    must pay for that benefit because it has “caused a part of those
    costs to be incurred, as without the expectation of its
    contributions the facilities might not have been built, or might
    5
    Section 309 provides that FERC “shall have power to perform any
    and all acts, and to prescribe, issue, make, amend, and rescind such
    orders, rules, and regulations as it may find necessary or appropriate
    to carry out the provisions of this chapter.” 16 U.S.C. § 825h.
    19
    have been delayed.” Ill. Com. Comm’n v. FERC, 
    576 F.3d 470
    ,
    476 (7th Cir. 2009) (cleaned up). The petitioners argue the
    stakeholders should pay for the upgrades they have used.
    Attachment Z2 implements the cost causation principle by
    requiring stakeholders who benefit from upgrades to pay for a
    share of the upgrades. The cost causation principle, however,
    concerns FERC’s approval of a rate as just and reasonable. K
    N Energy, Inc. v. FERC, 
    968 F.2d 1295
    , 1300 (D.C. Cir. 1992)
    (explaining the cost causation principle “add[s] flesh to the[]
    bare statutory bones” of the “just and reasonable” standard).
    The petitioners have provided no authority, nor have we found
    any, to suggest that a filed rate, which FERC found to be just
    and reasonable, can be waived because FERC later determines
    that its application violates the cost causation principle. Cost
    causation is a principle for ratemaking, not an abstract principle
    that can trump a filed rate.
    The petitioners wish FERC would have let things lie by
    permitting SPP to keep the upgrade charges it had already
    collected retroactively and distributed to upgrade sponsors like
    Oklahoma Gas. We recognize Oklahoma Gas and other
    sponsors of transmission upgrades relied on Attachment Z2,
    which provided that other utilities using and benefitting from
    the upgrades would share the costs of the upgrades. The
    upgrade sponsors cannot recover any costs for most of the
    historical period in which SPP was figuring out how to
    calculate the charges. Meanwhile, users who benefitted from
    the upgrades received a free pass during the historical period.
    Whatever the equities of this situation, the Commission’s
    decision to order the refund was a reasonable exercise of its
    remedial authority in light of its determination that the initial
    waiver violated the filed rate requirements and the upgrade
    charges would not have been collected but for that waiver. The
    outcome here should serve as a cautionary reminder to parties
    20
    that, if circumstances change, they should take action at the
    outset, such as by seeking to amend the tariff or requesting
    prospective waivers from FERC to act in contravention of a
    filed rate.
    We hold that FERC reasonably exercised its remedial
    authority to order SPP to refund the retroactive upgrade
    charges.
    ***
    The filed rate requirements are a formidable obstacle for
    entities regulated by FERC that wish to obtain retroactive relief
    from the terms of their tariff. The Commission correctly
    determined that Section I.7.1’s time bar was part of the filed
    rate. Therefore, the Commission lacked authority to provide a
    retroactive waiver and ordering a refund was a reasonable
    remedy. For the foregoing reasons, we deny the petitions.
    So ordered.