                             In the

    United States Court of Appeals
                For the Seventh Circuit
                   ____________________
Nos. 13-1944 & 13-2054
STEPHANIE SUE CARLSON,
                              Plaintiff-Appellant, Cross-Appellee,

                               v.

CSX TRANSPORTATION, INC.,
                       Defendant-Appellee, Cross-Appellant.
                   ____________________

       Appeals from the United States District Court for the
          Southern District of Indiana, Evansville Division.
     No. 3:11-cv-66-RLY-WGH — Richard L. Young, Chief Judge.
                   ____________________

     ARGUED MARCH 31, 2014 — DECIDED JULY 10, 2014
                   ____________________

   Before WOOD, Chief Judge, and WILLIAMS and HAMILTON,
Circuit Judges.
    HAMILTON, Circuit Judge. This appeal requires us to revis-
it the pleading requirements for discrimination and retalia-
tion claims under Title VII of the Civil Rights Act of 1964,
including claims for retaliation where the employee alleges
an ongoing pattern of retaliation. We must also clarify the
scope and effect of the Railway Labor Act’s mandatory arbi-
2                                      Nos. 13-1944 & 13-2054

tration provision when an employee alleges discrimination
or retaliation in violation of federal statutes.
    Plaintiff Stephanie Carlson brought several sex discrimi-
nation and retaliation claims under Title VII against her em-
ployer, defendant CSX Transportation, Inc., a railway com-
pany. She also brought a related contract claim based on the
settlement she had reached with CSX of an earlier discrimi-
nation lawsuit. CSX moved to dismiss, arguing that Carl-
son’s claims were implausible and that some were precluded
by the Railway Labor Act (RLA) because they were based on
company decisions justified by the terms of a collective bar-
gaining agreement.
    For the most part, the district court agreed with CSX,
dismissing the majority of Carlson’s claims for failure to state
a claim upon which relief could be granted and finding that
the RLA precluded the remaining claims. Carlson has ap-
pealed. We conclude that none of her claims should have
been dismissed. The allegations in her complaint are easily
sufficient to state claims for sex discrimination and retalia-
tion. And the RLA, which requires that claims arising under
collective bargaining agreements in the railway and airline
industries be decided in arbitration, does not preclude Carl-
son’s claims, which arise under Title VII and a private con-
tract between Carlson and CSX.
    Upon granting CSX’s motion to dismiss, the district court
also denied as moot a motion for summary judgment that
CSX had filed while its motion to dismiss was pending. CSX
has cross-appealed and asked us to grant summary judg-
ment in its favor if we conclude (as we do) that the district
court erred by dismissing Carlson’s claims on the pleadings.
We decline to rule on the summary judgment motion that
Nos. 13-1944 & 13-2054                                         3

the district court did not consider. We remand the case for
further proceedings.
I. Factual and Procedural Background
    We present the relevant facts based on Carlson’s allega-
tions, which we must accept as true on appeal from the grant
of a Rule 12(b)(6) motion to dismiss. E.g., Tellabs, Inc. v. Ma-
kor Issues & Rights, Ltd., 551 U.S. 308, 322 (2007); Luevano v.
Wal-Mart Stores, Inc., 722 F.3d 1014, 1027 (7th Cir. 2013). Carl-
son began her career with CSX in 2002 as a clerk. After seek-
ing unsuccessfully to advance in the company, she filed a
lawsuit in 2007 alleging sex discrimination. She was promot-
ed twice while that lawsuit was pending, first in 2008 to the
position of substitute yardmaster in Birmingham, Alabama,
and then in 2009 to the company’s manager trainee program.
In May 2009 while she was still in manager training, she and
CSX negotiated a settlement of her lawsuit. According to her
complaint, her superiors at CSX then made the training pro-
gram intolerable by belittling her, assigning her extra work,
and giving her unjustifiably poor evaluations, leaving her no
viable choice but to drop out.
    Upon leaving the training program, Carlson asked to be
reinstated as a substitute yardmaster in Birmingham. Her
request was denied. She alleges that the initial explanation
she received was that no positions were available, a conten-
tion that Carlson knew was untrue. Later a company repre-
sentative told her that she was denied the position because
she had not completed 60 “starts” (shifts) as a substitute
yardmaster when she previously held the position. But CSX
had allowed a male employee Carlson knows to return to a
substitute yardmaster position despite his not having com-
pleted 60 starts.
4                                      Nos. 13-1944 & 13-2054

    After learning that she could not resume work as a sub-
stitute yardmaster in Birmingham, Carlson took a lower-
paying position as a clerk in Evansville, Indiana. Two substi-
tute yardmaster positions were posted for Birmingham in
September 2009. Carlson applied for them but was rejected.
A company representative told her she was ineligible for the
positions because Birmingham was outside of her district,
though Carlson knows a male employee who was allowed to
transfer across districts. When substitute yardmaster posi-
tions later opened up in her district in Indiana, Carlson ap-
plied for those as well, but she was not even interviewed.
She alleges that the people ultimately hired for those posi-
tions were less qualified than she.
    Carlson filed charges with the Equal Employment Op-
portunity Commission regarding these events. After com-
pleting the EEOC process, she filed this federal lawsuit alleg-
ing violations of Title VII, see 42 U.S.C. § 2000e-2 (discrimi-
nation) and § 2000e-3 (retaliation), and state contract law.
(She actually filed suit in both Alabama and Indiana district
courts, but the suits were consolidated in the Southern Dis-
trict of Indiana.) She alleges that her poor treatment in man-
ager training amounted to a constructive demotion motivat-
ed by hostility to her sex and in retaliation for her EEOC
complaints and the 2007 lawsuit. She also alleges that CSX
for the same reasons refused to reinstate her to the substitute
yardmaster position she had previously held and refused to
select her for any of the substitute yardmaster positions that
opened up later. Her contract claim is that CSX breached a
no-retaliation clause of the agreement to settle her 2007 law-
suit.
Nos. 13-1944 & 13-2054                                        5

    In granting CSX’s motion to dismiss, the district court re-
jected most of Carlson’s claims under Federal Rule of Civil
Procedure 12(b)(6) for failure to state a claim upon which
relief could be granted. Carlson v. CSX Transp., Inc., No. 3:11-
cv-66-RLY-WGH, 2013 WL 869762, at *6–8 (S.D. Ind. Mar. 5,
2013). The only exceptions were her claims based on the de-
cision not to reinstate her as a substitute yardmaster in Ala-
bama immediately after she left the manager training pro-
gram. The court concluded that the discrimination claim was
plausible because Carlson had identified a male comparator
and that the retaliation claim was plausible because she was
denied the position within one month of the resolution of
her 2007 lawsuit. Regarding Carlson’s sex discrimination
claims relating to the other substitute yardmaster positions,
the court explained that she did not state plausible claims for
relief because each claim lacked either an allegation that the
position was filled by someone else or an allegation that the
person who filled the position was male. Her retaliation
claims relating to those positions, the court said, were im-
plausible because of the amount of time that had passed
(several months) between any protected activity and the de-
nial decisions.
    The court also explained that Carlson’s sex discrimination
and retaliation claims based on being forced out of the man-
ager training program were insufficient. No one at the pro-
gram had said anything about her sex or told her she would
be expelled from the program. Her allegations were “conclu-
sory,” the court wrote, and she had not provided “evidence
of intolerable working conditions.” Id. at *7. Moreover, Carl-
son had not cited any constructive demotion cases, i.e., cases
where an employee was forced out of a position yet re-
mained employed by the company. (The parties and the dis-
6                                      Nos. 13-1944 & 13-2054

trict court used the term “constructive discharge,” though a
more precise description of what Carlson alleges is construc-
tive demotion.)
    In dismissing her contract claim, the court gave two re-
lated reasons. Her allegations about the settlement agree-
ment were vague (intentionally so because she did not want
to risk a claim that she had breached the confidentiality
terms), and she had not fixed that problem by providing the
court a copy of the agreement.
    Returning to the two claims that had survived
Rule 12(b)(6)—sex discrimination and retaliation based on
CSX’s refusal to return her to the substitute yardmaster posi-
tion in Birmingham—the court dismissed them for lack of
subject matter jurisdiction. Id. at *8–9. The claims, the court
concluded, were precluded by the Railway Labor Act, which
requires that any claim of a railroad or airline employee that
is “grounded” in a collective bargaining agreement be de-
cided by an arbitrator. See Hawaiian Airlines, Inc. v. Norris,
512 U.S. 246, 256 (1994). CSX had argued in its motion to
dismiss that it acted in compliance with a collective bargain-
ing agreement when it refused to return Carlson to a substi-
tute yardmaster position. The district court found that CSX’s
explanation was enough to preclude the claims.
II. Timeliness of the Appeal
   CSX contends that Carlson’s notice of appeal was untime-
ly because she filed it more than 30 days after the district
court entered judgment against her. If CSX were correct, this
court would lack jurisdiction over her appeal. See Bowles v.
Russell, 551 U.S. 205, 209 (2007) (compliance with time limits
Nos. 13-1944 & 13-2054                                        7

on filing appeal is “mandatory and jurisdictional”). We find
that Carlson’s notice of appeal was timely.
    Judgment was entered on March 19, 2013. Within just a
few days, Carlson’s lawyers told her they would no longer
represent her, but they did not move to withdraw their ap-
pearances. Then on March 26 Carlson filed a pro se “motion
to reconsider,” explaining that her lawyers had quit and ask-
ing the court to reconsider the dismissal of her claims. She
said in the motion that she had actually submitted a copy of
the settlement agreement, and she argued that the court had
mistakenly accepted certain misrepresentations by CSX.
    On April 22, more than 30 days after the entry of judg-
ment, the district court entered an order “striking” Carlson’s
motion because she had signed it herself despite—
technically, at least—still being represented by counsel. See
Fed. R. Civ. P. 11(a). Two days later, Carlson’s lawyers finally
filed motions to withdraw, which the court granted. Then,
on May 1, nine days after the district court had stricken her
motion, new counsel for Carlson filed her notice of appeal.
    In a private civil case like this one, a party normally has
30 days from the entry of judgment to file a notice of appeal.
See Fed. R. App. P. 4(a)(1)(A). For Carlson that would have
been April 18. But if a party files a timely motion listed in
Federal Rule of Appellate Procedure 4(a)(4)(A), which in-
cludes a motion under Federal Rule of Civil Procedure 59(e)
to alter or amend a judgment, the 30-day window to appeal
runs from the time the district court “disposes” of the mo-
tion.
   Our jurisdiction therefore depends on the effect of Carl-
son’s pro se motion for reconsideration and the district court’s
8                                      Nos. 13-1944 & 13-2054

order striking it. A motion under Rule 59(e) need not be la-
beled as such or use the words “alter or amend” so long as it
“instead uses a synonym, such as ‘vacate’ or ‘reconsider.’”
Borrero v. City of Chicago, 456 F.3d 698, 699 (7th Cir. 2006).
Carlson filed a motion asking the district court to “reconsid-
er” its judgment one week after judgment was entered, well
within the 28 days Rule 59(e) allows.
    To counter this argument that the notice of appeal was
timely, CSX argues that Carlson’s motion could not toll the
time for filing the notice of appeal because the district court
dealt with the motion by striking it rather than denying it.
Relying on dictionary definitions of the word “strike,” CSX
sees Carlson’s stricken motion as a “nullity” that should be
treated as never having been filed at all. We reject this argu-
ment.
    The improper signature on Carlson’s motion was not an
error with jurisdictional consequences. The Supreme Court
held in Becker v. Montgomery, 532 U.S. 757, 765 (2001), that a
curable defect in a signature on a notice of appeal did not
render an appeal untimely. That logic easily extends to cura-
ble defects in signatures on post-judgment motions that af-
fect the time to file a notice of appeal. As the Court explained
in Becker, Rule 11(a), which the district court in this case re-
lied upon to strike Carlson’s motion, establishes that a defec-
tive signature on a filing may be cured. In fact, the rule al-
lows striking only after a missing signature is brought to the
attorney’s or party’s attention and is not promptly corrected.
The district court thus erred by not giving Carlson an oppor-
tunity to correct the defect in her motion. Moreover, under
Rule 4(a)(4)(A), the time to appeal runs from the entry of an
order “disposing” of a timely filed Rule 59(e) motion, and
Nos. 13-1944 & 13-2054                                         9

the district court’s order striking Carlson’s motion undenia-
bly disposed of it, whatever the meaning of the word
“strike.”
    In addition to those reasons, the district court’s error in
striking the motion sua sponte was also problematic here be-
cause Carlson’s lawyers had told her they would take no fur-
ther action on her behalf but had not withdrawn their ap-
pearances. She thus had no choice but to file the motion her-
self. Although “hybrid representation” (i.e., a represented
party filing papers on her own) is generally to be avoided,
see United States v. Chavin, 316 F.3d 666, 671–72 (7th Cir.
2002), summarily striking sua sponte a pro se filing that alerts
the court to an attorney’s withdrawal is unwarranted. The
fact that Carlson’s lawyers were slow to withdraw formally
should not have been held against her.
    CSX offers an additional argument that Carlson’s motion
for reconsideration could not toll the time to appeal. It ar-
gues that the motion was too insubstantial to qualify as a
motion under Rule 59(e). But only in extreme cases where a
motion was completely devoid of substance—meaning that it
did not identify a single reason, even a bad one, for the court
to reconsider its judgment—have we held that it did not toll
the time to appeal. See Talano v. Northwestern Medical Faculty
Foundation, Inc., 273 F.3d 757, 760–61 (7th Cir. 2001); Mar-
tinez v. Trainor, 556 F.2d 818, 819–20 (7th Cir. 1977). Carlson’s
motion asked the court to reconsider its judgment for sub-
stantive reasons (for example because the court had over-
looked that she had submitted a copy of her settlement
agreement), easily qualifying it as a Rule 59(e) motion. See
Blue v. Hartford Life & Accident Ins. Co., 698 F.3d 587, 598 (7th
Cir. 2012) (explaining that one basis for a Rule 59(e) motion
10                                       Nos. 13-1944 & 13-2054

is that “the court committed a manifest error of law or fact”).
To require more from a motion than an identifiable reason
for reconsidering (regardless of the reason’s merit) would
create troublesome uncertainty about when a notice of ap-
peal must be filed and would invite sterile litigation over
when unsuccessful motions to reconsider were too weak to
toll the time to appeal. We decline to go any further down
that road.
III. Sufficiency of Claims under Rule 12(b)(6)
    To analyze the sufficiency of a complaint we must con-
strue it in the light most favorable to the plaintiff, accept
well-pleaded facts as true, and draw all inferences in the
plaintiff's favor. Tamayo v. Blagojevich, 526 F.3d 1074, 1081
(7th Cir. 2008). A claim must be plausible rather than merely
conceivable or speculative, see Ashcroft v. Iqbal, 556 U.S. 662,
678 (2009); Bell Atlantic Corp. v. Twombly, 550 U.S. 544, 556
(2007), meaning that the plaintiff must include “enough de-
tails about the subject-matter of the case to present a story
that holds together,” Swanson v. Citibank, N.A., 614 F.3d 400,
404–05 (7th Cir. 2010). But the proper question to ask is still
“could these things have happened, not did they happen.” Id.
    In rejecting all but two of Carlson’s claims for failing to
state a plausible claim for relief, the district court applied the
wrong standard. The court repeatedly faulted her for not
providing “evidence” in support of her claims, see Carlson,
2013 WL 869762, at *6–7, though of course evidence is not
required at the pleading stage. And the court relied on
summary judgment decisions that addressed not the content
of complaints but the evidence needed to take a claim to a
jury. E.g., Kulumani v. Blue Cross Blue Shield Ass’n, 224 F.3d
681, 683 (7th Cir. 2000); Morrow v. Wal-Mart Stores, Inc.,
Nos. 13-1944 & 13-2054                                         11

152 F.3d 559, 561 (7th Cir. 1999); and Geier v. Medtronic, Inc.,
99 F.3d 238, 240 (7th Cir. 1996). The judicial pen may some-
times slip inadvertently in these ways, but in this case the
slips signaled accurately that the court had applied too de-
manding a standard. We assess Carlson’s claims under the
proper standard for Rule 12(b)(6) determinations.
   A. Sex Discrimination Claims Relating to Substitute Yard-
      master Positions
    A complaint alleging sex discrimination under Title VII
“need only aver that the employer instituted a (specified)
adverse employment action against the plaintiff on the basis
of her sex.” Tamayo, 526 F.3d at 1084; see also EEOC v. Con-
centra Health Services, Inc., 496 F.3d 773, 781–82 (7th Cir. 2007)
(stressing the simplicity of pleading a Title VII discrimina-
tion claim). The plaintiff is not required to include allega-
tions—such as the existence of a similarly situated compara-
tor—that would establish a prima facie case of discrimina-
tion under the “indirect” method of proof. Swierkiewicz v.
Sorema N.A., 534 U.S. 506, 511–12 (2002); see also Luevano v.
Wal-Mart Stores, Inc., 722 F.3d 1014, 1028 (7th Cir. 2013) (ob-
serving that Swierkiewicz survived Twombly and Iqbal); Swan-
son, 614 F.3d at 404 (same). While fraud claims, for example,
must be pled with particularity, see Fed. R. Civ. P. 9(b), Ti-
tle VII claims are not subject to a heightened pleading stand-
ard. Swierkiewicz, 534 U.S. at 513–15. Employers are familiar
with discrimination claims and know how to investigate
them, so little information is required to put the employer on
notice of these claims. Concentra, 496 F.3d at 782.
   In Carlson’s second amended complaint (the operative
one), she alleged which positions she sought and was de-
nied, and she attributed the denial to sex discrimination, sat-
12                                           Nos. 13-1944 & 13-2054

isfying the standard applied in Swanson, Tamayo, and Concen-
tra. She then provided additional allegations (which we
must accept as true at this stage) that were not needed but
bolstered the plausibility of her claims. These include that a
male employee was allowed to resume work as a substitute
yardmaster without having completed 60 starts and that an-
other man was allowed to transfer across districts, both
things Carlson was not allowed to do. Also casting doubt on
the honesty of CSX’s explanations for not promoting her are
Carlson’s allegations that the company gave her different
reasons at different times regarding the same job opening.
Inconsistent explanations by an employer can support a rea-
sonable inference of pretext that can defeat a motion for
summary judgment. E.g., Mullin v. Temco Machinery, Inc.,
732 F.3d 772, 778 (7th Cir. 2013) (reversing summary judg-
ment for employer); Hitchcock v. Angel Corps, Inc., 718 F.3d
733, 738 (7th Cir. 2013) (same).
     B. Retaliation Claims Relating to Substitute Yardmaster
        Positions
    Pleading a retaliation claim under Title VII requires the
plaintiff to “allege that she engaged in statutorily protected
activity and was subjected to an adverse employment action
as a result.” Luevano, 722 F.3d at 1029. 1 The protected activity

1 Following University of Texas Southwestern Medical Center v. Nassar, 133
S. Ct. 2517, 2534 (2013), the protected activity of an employee making a
retaliation claim must have been “a but-for cause of the alleged adverse
action by the employer.” (As opposed to the “lessened causation stand-
ard” that applies in Title VII discrimination cases. Id. at 2526.) The re-
quirement of but-for causation in retaliation claims does not mean that
the protected activity must have been the only cause of the adverse ac-
tion. Rather, it means that the adverse action would not have happened
without the activity. See id. at 2525.
Nos. 13-1944 & 13-2054                                        13

must be specifically identified. Concentra, 496 F.3d at 781.
Carlson’s retaliation claims relating to the substitute yard-
master positions include the allegations supporting her dis-
crimination claims, supplemented by the allegation that her
employer’s actions were caused by protected activity, name-
ly, her EEOC complaints and her lawsuit that began in 2007
and was settled in 2009.
    The district court found Carlson’s retaliation claim about
not being reinstated as a substitute yardmaster when she left
the training program to be plausible because CSX’s refusal to
reinstate her came less than a month after she and the com-
pany agreed to a settle her earlier lawsuit. But the court con-
cluded that the five months separating the resolution of the
lawsuit and the first of Carlson’s later substitute yardmaster
applications rendered her other retaliation claims implausi-
ble. Five months—“with no other evidence suggesting the
protected conduct provoked CSX’s retaliation”—was too
long for the events to be connected, the court reasoned, be-
cause four months was too long under Hughes v. Derwinski,
967 F.2d 1168 (7th Cir. 1992).
    In Hughes, we affirmed the grant of summary judgment
on a retaliation claim for the employer because, “standing by
itself,” four months between the employee’s protected activi-
ty and his discipline could not support an inference that the
two events were related. Id. at 1174–75. The “inference of
causation weakens as the time between the protected expres-
sion and the adverse action increases, and then ‘additional
proof of a causal nexus is necessary.’” Oest v. Illinois Dep’t of
Corrections, 240 F.3d 605, 616 (7th Cir. 2001), quoting Da-
vidson v. Midelfort Clinic, Ltd., 133 F.3d 499, 511
(7th Cir. 1998). Even intervals shorter than four months are
14                                      Nos. 13-1944 & 13-2054

unlikely, standing alone, to establish the causation element
of a retaliation claim. See Cung Hnin v. TOA (USA), LLC, 751
F.3d 499, 508 (7th Cir. 2014) (“Under most circumstances,
suspicious timing alone does not create a triable issue on
causation … .”).
     Although the district court once again seemed to require
evidence at the pleading stage and, in citing only Hughes, re-
lied exclusively on a summary judgment case, a retaliation
claim can indeed be so bare-bones that a lengthy time period
between the protected activity and the alleged retaliation
will make any causal connection between the two implausi-
ble. If the best a plaintiff can do is allege that he engaged in
protected activity and then, years later, the employer took an
adverse action against him, the claim may not be permitted
to proceed. See, e.g., Carmody v. Board of Trustees of Univ. of
Illinois, 747 F.3d 470, 480 (7th Cir. 2014) (unexplained three-
year gap between employee’s report against another em-
ployee and his termination made state-law retaliation claim
implausible where focus of case was much more immediate
dispute, including full due-process hearing, over whether
employee had breached security of employer’s computer
network).
    But no bright-line timing rule can be used to decide
whether a retaliation claim is plausible or whether it should
go to a jury. Other factors can always be relevant. “A mecha-
nistically applied time frame would ill serve our obligation
to be faithful to the legislative purpose of Title VII. The facts
and circumstances of each case necessarily must be evaluat-
ed to determine whether an interval is too long to permit a
jury to determine rationally that an adverse employment ac-
Nos. 13-1944 & 13-2054                                       15

tion is linked to an employee’s earlier complaint.” Oest,
240 F.3d at 616.
    In this case, Carlson has alleged that the resolution of her
2007 lawsuit in 2009 sparked animosity right away and that
all of her attempts to advance at CSX since then have been
thwarted. She has described an ongoing campaign of retalia-
tion, and her claims must be viewed through that lens. See,
e.g., Warren v. Prejean, 301 F.3d 893, 900 (8th Cir. 2002) (af-
firming jury verdict for plaintiff on retaliation claim because,
despite over four-year gap between grievance and termina-
tion, termination “was the end result of an ongoing pattern of
retaliatory behavior”); Woodson v. Scott Paper Co., 109 F.3d
913, 920–21 (3d Cir. 1997) (affirming jury verdict for plaintiff
on retaliation claim because “a plaintiff can establish a link
between his or her protected behavior and subsequent dis-
charge if the employer engaged in a pattern of antagonism in
the intervening period,” even if the intervening period
spanned years).
   Carlson’s allegations convinced the district court that
CSX’s initial refusal to reinstate her as substitute yardmaster
may have been retaliatory, but the court then concluded that
the company’s refusal to hire her for the same position a few
months later could not possibly have been retaliatory be-
cause of the time that had passed. This parsing of events lost
sight of the bigger picture, which showed an ongoing pat-
tern of retaliation. Under these circumstances, we conclude
that all of Carlson’s retaliation claims are plausible and sur-
vive Rule 12(b)(6).
16                                     Nos. 13-1944 & 13-2054

     C. Claims Relating to Training Program
     Also plausible are Carlson’s sex discrimination and retal-
iation claims relating to the manager training program, from
which she withdrew just before seeking to resume work as a
substitute yardmaster. According to Carlson’s complaint, she
was treated so poorly in CSX’s manager training program
that she was effectively forced out. She alleges that the poor
treatment was motivated by her sex and by her 2007 lawsuit,
which the parties agreed to settle in 2009 while she was in
the training program. Her supervisors in the training pro-
gram were aware of the settlement negotiations because she
had to take time off to attend them, and the supervisors’ hos-
tility toward her increased substantially upon her return
from the successful negotiations.
    The district court concluded that her allegations of regu-
lar belittlement, unfair criticism, and unduly poor assess-
ments were insufficient to support either claim. No one had
said anything overtly sexist or told Carlson’s that she would
soon be dismissed from the program. Her allegations were
“conclusory,” the court said, and she did not offer “evidence
of intolerable working conditions.” Nor did Carlson cite cas-
es involving employees who were forced out of a position
but not out of the company.
    These were not sufficient reasons for dismissing Carlson’s
claims on the pleadings. Even if a claim might theoretically
be too “conclusory”—a theory hard to square with
Swierkiewicz and Swanson, at least where the situation is
identified and unlawful motivation alleged—Carlson in-
cluded specific examples of poor treatment. A work envi-
ronment, it is true, must be “intolerable” to support a con-
structive discharge claim. See Chapin v. Fort-Rohr Motors, Inc.,
Nos. 13-1944 & 13-2054                                        17

621 F.3d 673, 679 (7th Cir. 2010). The conditions Carlson de-
scribed in her complaint may not ultimately qualify as intol-
erable, but we cannot say so definitively at the pleading
stage, which (we stress again) is before any evidence is re-
quired. And although “constructive demotion” (what Carl-
son has actually asserted) is an unusual claim, it is nonethe-
less a viable legal theory. See Simpson v. Borg-Warner Automo-
tive, Inc., 196 F.3d 873, 876 (7th Cir. 1999) (“[A] constructive
demotion analysis should have the same structure as that for
constructive discharge.”).
    Before moving on to the contract claim and the RLA is-
sues, we also note that all the discrimination and retaliation
claims in Carlson’s first amended complaint also satisfied
Rule 12(b)(6). The district court simply demanded too much
at the pleading stage here, resulting in further efforts at
pleading to reach a standard that is rarely realistic before
discovery. This case therefore illustrates well the important
distinction the Supreme Court drew in Swierkiewicz be-
tween pleading requirements and evidentiary requirements.
534 U.S. at 510–12 (holding that plaintiff need not plead ele-
ments of prima facie case under indirect proof method).
    To illustrate this point, consider the need to identify simi-
larly situated employees as part of the prima facie case un-
der the indirect proof method. As we explained in Coleman v.
Donahoe, 667 F.3d 835, 847–50 (7th Cir. 2012), the identity of
the employer’s decision-maker and the employer’s stated
reason for its decision are critical in figuring out who else
might have been similarly situated. The employee often will
not be able to answer those questions without discovery. See
Cloe v. City of Indianapolis, 712 F.3d 1171, 1184–85 (7th Cir.
2013) (Hamilton, J., concurring). The plaintiff is not required
18                                        Nos. 13-1944 & 13-2054

to identify similarly situated comparators at the pleading
stage. And the very complexity of the dance between the in-
terdependent steps of the indirect proof method supports
Chief Judge Wood’s suggestion in her concurrence in Cole-
man that it is time to collapse the different methods of proof
into one test: whether a rational jury could find that the em-
ployer took action against the plaintiff for an unlawful rea-
son. 667 F.3d at 862–63.
     D. Contract Claim
    Carlson explained in her complaint that her contract
claim was intentionally vague because she was bound by a
confidentiality clause in the settlement agreement. She asked
the court to allow her to submit the settlement agreement for
in camera review. The district court dismissed the claim on
the basis that Carlson never provided a copy of the agree-
ment. But as Carlson first pointed out in her Rule 59(e) mo-
tion—and as the record confirms—she did submit the
agreement under seal to the district court. Thus the court’s
dismissal of this claim must be reversed as well. (During oral
argument, Carlson’s lawyer acknowledged that the contract
claim stands or falls with the retaliation claims. It is not clear
how much the claim adds to the case, but that can be ad-
dressed later.)
IV. Preclusion by the Railway Labor Act
    Two claims survived the district court’s scrutiny under
Rule 12(b)(6): Carlson’s discrimination and retaliation claims
relating to CSX’s failure to reinstate her as substitute yard-
master just after she left the manager training program.
These claims, the court determined, were precluded by the
Railway Labor Act (RLA), which requires that certain claims
Nos. 13-1944 & 13-2054                                          19

be resolved through arbitration under the Act. The court
dismissed the claims for lack of subject matter jurisdiction.
   A. Jurisdictional Requirement?
    Before addressing whether any of Carlson’s claims were
in fact subject to mandatory arbitration, we briefly call atten-
tion to the issue whether a party’s failure to comply with the
RLA’s arbitration provision deprives federal courts of subject
matter jurisdiction rather than simply defeats the claim. The
distinction between the two grounds for dismissal is incon-
sequential in this case, where waiver is not an issue because
the defendant argued RLA preclusion at every stage, but it
could matter in others.
     The district court, in treating the RLA’s arbitration re-
quirement as jurisdictional, naturally followed this court’s
practice of referring to the requirement in those terms. See,
e.g., Brotherhood of Maintenance of Way Employees Division/IBT
v. Norfolk Southern Ry. Co., 745 F.3d 808 (7th Cir. 2014); Brown
v. Illinois Central R.R. Co., 254 F.3d 654 (7th Cir. 2001). But our
longstanding practice under the RLA has not yet taken into
account the lesson of Arbaugh v. Y&H Corp., 546 U.S. 500
(2006), and other similar cases in which the Supreme Court
has explained that many statutory requirements that have
been termed “jurisdictional” are actually just elements that
must be satisfied for a plaintiff to prevail. “Jurisdiction” is a
word with “many, too many, meanings,” and a proper ruling
on whether a party’s failure to meet a statutory requirement
deprives federal courts of subject matter jurisdiction must be
based on whether Congress clearly indicated that it was set-
ting a jurisdictional limitation. Id. at 510–11, 515–16.
20                                      Nos. 13-1944 & 13-2054

    When a future case requires a decision on whether the
RLA’s arbitration provision is jurisdictional, we will need to
consider carefully the opposing positions recently taken on
the issue by the D.C. and Sixth Circuits. Compare Oakey v.
US Airways Pilots Disability Income Plan, 723 F.3d 227 (D.C.
Cir. 2013) (RLA arbitration requirement is jurisdictional),
with Emswiler v. CSX Transportation, Inc., 691 F.3d 782
(6th Cir. 2012) (not jurisdictional). We need not and do not
decide the issue in this case.
     B. Claims Grounded in the Collective Bargaining Agreement?
    Congress passed the RLA, which governs railroads and
airlines, to provide for “the prompt and orderly settlement”
of labor disputes in those industries. 45 U.S.C. § 151a; see
Hawaiian Airlines, Inc. v. Norris, 512 U.S. 246, 252 (1994)
(“Congress’ purpose in passing the RLA was to promote sta-
bility in labor-management relations by providing a com-
prehensive framework for resolving labor disputes.”). To
that end, the Act requires that so-called “minor disputes” be
resolved in arbitration before an adjustment board estab-
lished by the employer and union rather than in court. Ha-
waiian Airlines, 512 U.S. at 252; Atchison, Topeka & Santa Fe Ry.
Co. v. Buell, 480 U.S. 557, 563, 566 (1987); Brown, 254 F.3d at
658. Minor disputes are those “growing out of grievances or
out of the interpretation or application of agreements con-
cerning rates of pay, rules, or working conditions.” 45 U.S.C.
§ 153 First (i). In other words, minor disputes are those
“grounded in” a collective bargaining agreement. Hawaiian
Airlines, 512 U.S. at 256. (By contrast a “major dispute” is one
involving the formation or modification of a collective bar-
gaining agreement. Id. at 252; Chicago & North Western
Nos. 13-1944 & 13-2054                                      21

Transp. Co. v. Railway Labor Executives’ Ass’n, 908 F.2d 144,
148 (7th Cir. 1990).)
    In this case we must fit Title VII claims into this frame-
work, taking care not to interpret the RLA as excluding a
class of employees from statutory protections against em-
ployment discrimination and retaliation. CSX’s position is
that the RLA precludes Carlson’s Title VII claims simply be-
cause the company says that, in refusing to reinstate Carlson
as a substitute yardmaster, it acted pursuant to a collective
bargaining agreement rather than for discriminatory or retal-
iatory reasons. Carlson’s position is that the RLA does not
preclude her claims because she is not asserting any right
under the collective bargaining agreement, which in any
event does not itself prohibit sex discrimination or retalia-
tion.
    The Supreme Court’s decision in Hawaiian Airlines pro-
vides important guidance. The plaintiff in Hawaiian Airlines
was an airline mechanic who was fired after he refused to
sign a maintenance record when he believed the airplane
was still not safe. He sued his former employer for wrongful
discharge under a state whistleblower law and a public poli-
cy exception to employment at will. The employer contend-
ed that the RLA preempted the plaintiff’s claim because his
discharge may have been justified under the collective bar-
gaining agreement. The Supreme Court rejected that argu-
ment: a claim based on a right that is “independent” of a col-
lective bargaining agreement is not subject to mandatory ar-
bitration, and a claim is independent if it cannot be “conclu-
sively resolved” by interpreting the collective bargaining
agreement. Hawaiian Airlines, 512 U.S. at 263, 265. This analy-
sis applies regardless of whether the independent right as-
22                                     Nos. 13-1944 & 13-2054

serted is based on state or federal law. The Court made this
clear in Hawaiian Airlines by reaffirming the holding of
Atchison, Topeka and Santa Fe Ry. Co. v. Buell that the RLA
does not preclude claims under the Federal Employers’ Lia-
bility Act even when the employee may also have a claim
based on the same facts under the collective bargaining
agreement. See 512 U.S. at 258–59, citing Buell, 480 U.S. at
564–65.
     The line drawn in Hawaiian Airlines—disputes over rights
under a collective bargaining agreement must be resolved by
an arbitrator while claims based on rights with an independ-
ent basis may be litigated as usual—is generally easy to dis-
cern. On occasion, however, a claim is brought under state or
federal law that in reality asserts rights established by a col-
lective bargaining agreement. For example, in Tice v. Ameri-
can Airlines, Inc., 288 F.3d 313, 316–17 (7th Cir. 2002), we
found that the employees’ claims under the Age Discrimina-
tion in Employment Act were precluded because they relied
on a contention that the collective bargaining agreement en-
titled the employees to certain positions. And sometimes a
nominally independent claim can be “conclusively resolved”
by interpreting a collective bargaining agreement because
the claim’s success depends entirely on the agreement’s
meaning. See Brown, 254 F.3d at 660–61. In Brown, the plain-
tiff’s accommodation request under the Americans with Dis-
abilities Act (ADA) “might very well violate the seniority
system established by the CBA,” and the ADA does not re-
quire accommodations that interfere with the seniority rights
of other employees. Id. at 661; see Eckles v. Consolidated Rail
Corp., 94 F.3d 1041, 1046 (7th Cir. 1996). The “heart of the
dispute” in Brown, we explained, was “a disagreement over
Nos. 13-1944 & 13-2054                                         23

the interpretation” of a collective bargaining agreement.
254 F.3d at 664.
    Carlson’s claims do not fall into the exception illustrated
by Tice and Brown to the general rule that the RLA does not
require arbitration of claims asserting rights established by
state or federal law independent of a collective bargaining
agreement. Unlike the plaintiff in Tice, Carlson does not
claim that she was entitled to a particular job under the col-
lective bargaining agreement. She alleges that her applica-
tions were rejected because of her sex and in retaliation for
protected activity, in violation of Title VII. Her claims thus
depend on a “factual inquiry into any retaliatory [or discrim-
inatory] motive of the employer” rather than on an interpre-
tation of the collective bargaining agreement. See Hawaiian
Airlines, 512 U.S. at 266 (finding such claims are not preclud-
ed or preempted by RLA).
     CSX argues that Carlson’s claims could be conclusively
resolved by an arbitral ruling that she was not qualified un-
der the collective bargaining agreement to be a substitute
yardmaster, making her claims equivalent to those in Brown.
The argument is based on a misunderstanding of the nature
of her claims. Even if Carlson did not have the qualifications
specified in the collective bargaining agreement, she would
still have viable Title VII claims if, as she alleges, the same
potentially disqualifying attributes have been overlooked for
men or for others who have not complained about discrimi-
nation. See Rabé v. United Air Lines, Inc., 636 F.3d 866, 873 (7th
Cir. 2011) (holding that a flight attendant’s claim that a col-
lective bargaining agreement’s voucher policy was enforced
against her discriminatorily in violation of Title VII was not
precluded by the RLA because the claim did not “call the
24                                     Nos. 13-1944 & 13-2054

policy itself into dispute”); Carmona v. Southwest Airlines Co.,
536 F.3d 344, 349–50 (5th Cir. 2008) (claims under Title VII
avoided RLA preclusion because plaintiff alleged “that CBA
procedures were applied in a discriminatory manner, not that
CBA procedures were fundamentally discriminatory”).
    As we were careful to clarify in Brown, a claim is not
barred simply because “the action challenged by the plaintiff
is ‘arguably justified’ by the terms of the CBA.” 254 F.3d at
668, quoting Hawaiian Airlines, 512 U.S. at 265–66. An “em-
ployer cannot ensure the preclusion of a plaintiff’s claim
merely by asserting certain CBA-based defenses to what is
essentially a non-CBA-based claim.” Id. at 668. And the fact
that a collective bargaining agreement might be consulted in
resolving a plaintiff’s claims is insufficient to trigger RLA
preclusion. Claims are not precluded just “because certain
provisions of the CBA must be examined and weighed as a
relevant but non-dispositive factor in deciding a claim or a
defense.” Id.
    All this is to say that RLA preclusion, properly applied,
does nothing more than keep disputes actually arising under
a collective bargaining agreement out of court. Employees
may enter into a contract requiring that other types of claim
be brought only in arbitration, but if a collective bargaining
agreement simply prohibits employers from doing some-
thing (for example discriminating on a certain basis) or
merely allows arbitration of some type of claim, a claim un-
der an independent law covering the same subject matter is
not precluded. See Felt v. Atchison, Topeka & Santa Fe Ry. Co.,
60 F.3d 1416, 1419 (9th Cir. 1995) (Title VII claim of religious
discrimination was not precluded simply because the collec-
tive bargaining agreement “provides for arbitration of claims
Nos. 13-1944 & 13-2054                                       25

of religious discrimination”); see also Hawaiian Airlines,
512 U.S. at 262–63 (explaining that a wrongful discharge
claim based on state law can go forward even if it depends
on the same facts as a wrongful discharge claim under a col-
lective bargaining agreement).
    So Carlson’s claims under Title VII could proceed in fed-
eral court even if the collective bargaining agreement pro-
hibited sex discrimination and retaliation. Notably, however,
the collective bargaining agreement in this case (as CSX con-
ceded at oral argument) does not prohibit sex discrimination
or retaliation, meaning that CSX is making a truly radical
argument: that Carlson cannot assert in any forum her right
to be free from sex discrimination and retaliation. We can see
no reason to apply the RLA in a way that, in addition to hav-
ing no basis in the text, would lead to that extraordinary re-
sult.
V. CSX’s Motion for Summary Judgment
    In its cross-appeal, CSX asks that we grant summary
judgment in its favor if we should decide that Carlson’s
claims were erroneously dismissed. We have so decided, but
we decline to take the unusual step of ruling on a summary
judgment motion that the district court has not considered,
especially one as fact-intensive as this one. The district court
should take the first crack at it. On remand, however, a new
briefing schedule for summary judgment motions will need
to be set because no motion for summary judgment is cur-
rently pending. (The district court denied CSX’s motion as
moot.) Because our decision also reshapes the case by restor-
ing the claims erroneously dismissed on RLA grounds, the
court should reopen discovery so that Carlson can gather
26                                  Nos. 13-1944 & 13-2054

and present additional evidence now that she is represented
by new counsel.
   The district court’s dismissal of Carlson’s claims is
REVERSED and the case is REMANDED for further pro-
ceedings consistent with this opinion.
