                              In the

    United States Court of Appeals
                 For the Seventh Circuit
No. 16-2939

STEVEN A. LAUTH,
                                                Plaintiff-Appellant,

                                v.


COVANCE, INC.,
                                               Defendant-Appellee.


         Appeal from the United States District Court for the
          Southern District of Indiana, Indianapolis Division.
     No. 1:14-cv-00136-WTL-TAB — William T. Lawrence, Judge.



     ARGUED FEBRUARY 7, 2017 — DECIDED JULY 13, 2017


   Before BAUER, POSNER, and SYKES, Circuit Judges.
    BAUER, Circuit Judge. Steven Lauth was terminated from his
position at Covance Central Laboratories, Inc. on October 25,
2012. He sued Covance, raising claims of age discrimination
and retaliation. The district court granted summary judgment
in favor of Covance. The court also awarded certain costs to
Covance. Lauth appeals from both orders.
2                                                 No. 16-2939

                     I. BACKGROUND
   The facts that follow are those established by the summary
judgment record in the district court, as viewed in the light
most favorable to Lauth. See Whitaker v. Wis. Dep’t of Health
Servs., 849 F.3d 681, 682 (7th Cir. 2017).
   Lauth began working at Covance in 2006 at the age of 54.
He started as a second shift supervisor in the kit production
department. From the time Lauth started in 2006 through April
2012, Donald Snyder was his direct supervisor.
     After the end of each year, and sometimes at mid-year,
Lauth received a performance review called a Performance
Management Document (PMD). Snyder, as Lauth’s supervisor,
wrote his first review in 2006 and issued Lauth an overall
rating of “Meets Expectations.” He praised Lauth for maximiz-
ing his department’s output and for his “diligence in getting
his staff cross trained as much as possible.” Snyder also
commented on Lauth’s communication style, noting that he
“need[s] to tailor or soften somewhat his approach, to that of
his workforce.” He stated that Lauth could do this by “using a
little more compassion and maybe even incorporating ways to
relax the 2nd shift.” Finally, Snyder noted that Lauth needed
“to realize and make any necessary adjustments in his style, in
order to match the environment of the 2nd shift workforce,
without comprimising [sic] his beliefs and standards.”
    In Lauth’s 2007 PMD, Snyder again gave him a “Meets
Expectations” overall rating. Snyder praised Lauth’s diligence,
work ethic, and “all business approach” to his job. However,
the PMD also noted improvements that Lauth needed to make
in his communication style. Snyder noted that several staff
No. 16-2939                                                     3

members had expressed their discontent with Lauth’s supervi-
sion and communication style; Snyder stated that Lauth “will
need, and has begun, to tailor or soften somewhat his approach
to that of his workforce.” Snyder also commented that Lauth
“is at times unreceptive to take help and/or suggestions from
others, choosing to do it his way. This is often not received well
with his peers.”
    Lauth received an overall rating of “Meets Expectations”
again in 2008. Snyder commented that Lauth was able to
accomplish his department’s output with the least experienced
and fewest number of employees. He also noted that morale
“no longer seems to be an issue within [Lauth’s] shift, regard-
ing his supervision and communication style.” However,
Snyder also reiterated his concerns that Lauth “appears
unreceptive to take help and/or suggestions from others” and
stated that Lauth “must improve … [his] working relationship
with his fellow shift supervisors.” Because Lauth’s style was
often not well-received by his peers, Snyder stated that “I
actually wonder whether or not if [Lauth] is the right fit for our
team.” In this PMD, Snyder warned that if Lauth’s “tempera-
ment and communication practices” did not change, “this may
impact his rating for next year, or potentially run the risk of
[Snyder] needing to replace him with someone who works
better with the others in the room, across all facets.”
    In 2009, Lauth again received a rating of “Meets Expecta-
tions.” In 2010, however, he received a rating of “Exceeds
Expectations.” Snyder praised Lauth for leading all shift’s in
total output, noting that he played a “huge role in [kit produc-
tion]’s overall departmental success in 2010.” He also noted
that Lauth had done a good job avoiding conflict with other
4                                                  No. 16-2939

staff. Finally, however, Snyder commented that Lauth is “very
strong willed and an independent thinker,” which “[a]t times
… can be confused or perceived to be detrimental to the
cause.”
    On July 11, 2011, Lauth received a mid-year PMD from
Snyder, which again complimented Lauth for meeting his
unit’s output goals. However, Snyder also provided detailed
comments regarding issues with Lauth’s communication
methods and his unwillingness to be a “team player.” Specifi-
cally, Snyder mentioned emails that Lauth had sent during the
first half of 2011, in which Lauth addressed noise issues in his
department. Snyder noted that “[a]lthough I know [Lauth’s]
intent was fine, the manner [in] which the emails were written
and perceived, [was] counterproductive.” Snyder also noted a
specific instance in which Lauth challenged one of Snyder’s
directives and expressed an inability to complete an assigned
task. In the “Team Player” category, Snyder stated that
“[Lauth’s] ‘my way’ approach is no longer acceptable to me.
This needs to change and improve this year. I want to see an
obvious change in [Lauth] relating to how he works with all
[kit production] leadership, otherwise, [Lauth] risks being
given a Needs Improvement rating at year end.” Shortly after
Snyder issued the mid-year PMD, he and Lauth met in person
to discuss it. During that meeting, Snyder asked Lauth when
he planned to retire.
   Covance had a system called AlertLine, through which
employees could submit workplace complaints. On August 28,
2011, Lauth submitted a complaint through AlertLine regard-
ing Aaron Ellsworth, another employee in the kit production
department. Between 2006 and 2011, Lauth had various verbal
No. 16-2939                                                    5

complaints to Snyder about Ellsworth, alleging that he bullied
and intimidated Lauth and other employees.
    In his AlertLine complaint, Lauth complained of Ells-
worth’s harassment, but specifically noted that it did not relate
“to unlawful harassment … because of race, color, religion,
national origin, gender, age, disability, veteran’s status or any
other characteristic protected by law[.]” Lauth cited examples
of “behavior that could be labeled ‘bullying’ and ‘intimidation’
contrary to Covance’s Principle of ‘Respect for the individual.’”
Additionally, Lauth stated the following in reference to his
2011 mid-year PMD:
       Due to the statements made by my manager in
       my review, I responded in an email specifically
       to my manager’s comments in a much more
       timid manner where I would normally have felt
       comfortable challenging some of his assertions,
       because I felt that I was being threatened—not
       truly because of my work performance being
       inadequate, but more due to the environment
       that exists in our department as a result of [Ells-
       worth]’s continued exhibits of control, intimida-
       tion and bullying. It was very clear that
       [Snyder]’s comments of being a team player
       were meant to communicate that I needed to
       ‘get along better’ with [Ellsworth]. … Although
       this abusive environment that [Ellsworth] has
       created exists and has been brought to
       [Snyder]’s attention on many occasions by
       myself and others, he has allowed the situation
       to continue.
6                                                   No. 16-2939

    Covance referred this complaint to Human Resources
Generalist Gary Grubb for investigation. Grubb completed
the investigation in late November or early December 2011. He
found that Ellsworth had behaved inappropriately on several
occasions, raising his voice and making inappropriate com-
ments. Grubb also found that Snyder had not mistreated
Lauth, and identified several areas in which Lauth could
improve his workplace communications. He recommended to
Snyder that Ellsworth be placed on a Performance Improve-
ment Plan (PIP).
    On December 2, 2011, Grubb met with Lauth to discuss the
findings of his investigation and inform him that Ellsworth
would be counseled on his behavior. On December 5, 2011,
Lauth sent Grubb an email stating that the proposed discipline
was “totally unacceptable” and expressing his belief that the
investigation had not gone far enough. On January 10, 2012,
Grubb’s findings and proposed corrective actions were posted
as follow-up comments to Lauth’s AlertLine complaint. On
January 11, 2012, Snyder placed Ellsworth on a PIP, which he
satisfactorily completed on May 18, 2012.
    On January 25, 2012, Lauth filed a charge of discrimination
with the Equal Employment Opportunity Commission. He
claimed that Covance discriminated against him on the basis of
his age, citing Snyder’s inquiry as to when he planned to retire.
Lauth also alleged that Covance retaliated against him for
making complaints about Ellsworth.
   The same day Lauth filed the EEOC charge, Snyder met
with him to discuss the outcome of his AlertLine complaint.
Snyder explained that Ellsworth had begun counseling, that
No. 16-2939                                                    7

they had given Ellsworth action items to work on, and that
they were monitoring him. Snyder also reiterated his concerns
with Lauth’s communication style and reminded him that the
issues discussed at the mid-year review still applied. Specifi-
cally, Snyder told Lauth that he was expected to be cordial to
everyone, including Ellsworth. A few hours later, Lauth
responded to Snyder in an email, stating that he was always
cordial to everyone and that it was Ellsworth who needed to
correct his behavior. Snyder replied by email, again explaining
that Ellsworth was being counseled. Snyder also stated that
Lauth would be subject to “Progressive Corrective Action” if
he initiated any “further non-professional, non-cordial con-
duct, [or] non-cooperative interactions” with Ellsworth.
    On January 20, 2012, Snyder completed Lauth’s 2011 year-
end PMD. Snyder gave Lauth an overall rating of “Meets
Expectations,” but again noted communication problems and
stated that Lauth had not done enough to change Snyder’s
assessment of these issues. He wrote that he “expect[s] to see
an obvious change in [Lauth] regarding how he works with
and communicates with all [kit production department]
employees.”
    On April 30, 2012, the EEOC issued Lauth a Dismissal and
Notice of Rights letter regarding his January 25, 2012, charge
of discrimination. The deadline to file suit with respect to that
charge was July 30, 2012, which passed without Lauth taking
action.
   Imelda Marsh assisted Snyder in the supervision of the kit
production department from April 2012 to July 2012, at which
time Snyder transitioned out of his role and was replaced by
8                                                  No. 16-2939

Christine Walters. On July 10, 2012, Marsh sent Grubb an email
regarding an interaction she witnessed between Lauth and
Walters. Marsh stated that Lauth “was argumentative and
insubordinate in his approach with [Walters].” She explained
that she planned to meet with Lauth and give him a PIP, but
also stated that she wanted approval to terminate his employ-
ment.
    Instead of terminating Lauth or giving him a PIP, Marsh
issued him a written warning on July 20, 2012. The warning
stated that it was “due to repeated inappropriate and unprofes-
sional communication.” It cited Lauth’s inability to receive
constructive feedback and “establish stable, manageable
working relationships with peers.” The warning concluded
that “[a]ny further incidents involving inappropriate and
unprofessional behavior/communication in maintaining a
positive non-confrontational relationship with others will
result in additional progressive corrective action, including
termination.”
    Marsh gave Lauth the written warning during a face-to-face
meeting, which Lauth audio-recorded. At one point during the
meeting, Lauth asked if he could prepare a written response to
the warning. Marsh responded by saying, “… this is not going
to work for me. … If I have to feel like I’m on trial with you
every time I have a conversation with you, if I feel like you’re
putting together a case, this is not the right place for you.”
    Walters replaced Snyder as the supervising manager of the
kit production department in July 2012. Before he left the
position, Snyder completed a mid-year PMD and a PIP for
Lauth. Walters delivered these documents to Lauth on
No. 16-2939                                                  9

August 8, 2012. The PMD indicated that Lauth was “tracking
towards a ‘Needs Improvement’ year end rating.” It stated
that Lauth “refused to change his communication practices,
despite being informed via PMD meetings numerous times.”
The PIP stated that it had been issued “due to on-going
concerns regarding [Lauth]’s performance and/or behavior.” It
cited examples of Lauth’s problematic behavior that had
occurred since his 2011 mid-year PMD. The PIP contained
“action steps” that Lauth was expected to complete within
ninety days, including providing appropriate and timely
communications, participating in leadership meetings, and
engaging in a more “proactive, outreaching approach” to
work-related concerns.
    Lauth audio-recorded the meeting in which Walters
provided these documents. When Walters asked him what he
thought of the documents, Lauth responded, “[w]ell, to me, it’s
all retaliatory. … There was no input, so this PIP, to me, is
frivolous, it’s a mistake.”
    Lauth went on vacation from September 1, 2012, through
September 17, 2012. Lauth filed a second charge of discrimina-
tion with the EEOC on September 17, 2012. Again, he alleged
age discrimination, based on Snyder’s retirement question,
and retaliation, based on the various reviews and warnings
he received since his first charge was filed and dismissed.
    While Lauth was on vacation, Ellsworth had an argument
on the production floor with Roger Carter, another kit produc-
tion employee. Ellsworth reported the incident to Walters, who
reported it to Human Resources and spoke with Ellsworth’s
shift supervisor about the incident. When he returned to work
10                                                  No. 16-2939

on September 18, 2012, Lauth had a meeting with Walters to
discuss his progress on his PIP. Lauth had learned about
the incident between Ellsworth and Carter and mentioned it
to Walters at their meeting. Walters assured Lauth that she
knew of the incident, had reported it to Human Resources, and
was handling its resolution. Despite this response, Lauth
proceeded to investigate the incident himself. Then, on
September 21, 2012, Lauth sent an email to Grubb reporting
the incident. Grubb responded on September 24, 2012, indicat-
ing that he was aware of the incident and that it was being
handled by Walters and the first-shift supervisor.
     On October 2, 2012, Walters held another PIP progress
meeting with Lauth. In that meeting, she told Lauth that she
would have liked him to trust her when she said that she was
handling the Ellsworth incident and that she would have liked
it if he had not investigated it himself. Lauth indicated that he
had been trying to get Ellsworth’s behavior corrected for six
years and stated that he had to make a record of the incident
for his own benefit. Walters said that she thought this behavior
was inconsistent with his PIP. Lauth disagreed, saying that he
did not think what he did was wrong or unprofessional. He
also reiterated his belief that he should not have been placed
on a PIP at all.
    Between October 8 and October 17, 2012, Walters received
complaints from four of Lauth’s second-shift kit production
employees. On October 8, 2012, Kathleen Kiemeyer told
Walters that Lauth had been harassing her, and that he was
unapproachable and intimidating. On October 9, 2012, Rhonda
Taylor, a new employee at the time, described Lauth as
intimidating and requested that she be transferred out of his
No. 16-2939                                                11

department. On October 12, 2012, Cassandra Wilson told
Walters that Lauth had written her up for an error she made
while on her third day of training, which she believed was
unfair. She also described Lauth as intimidating and said that
he made her uncomfortable because he would stand near her
and watch her work. Finally, on October 17, 2012, Tammy
Wright, another kit production employee, complained that
she was not receiving adequate training.
   On October 18, 2012, Walters and Heidi Sturgeon, a Human
Resources employee, met with Lauth to discuss these com-
plaints. Lauth stated that he was unhappy with how these
complaints were addressed because he could not investigate
them himself. He also requested that Walters interview other
employees on his shift to see whether they agreed with these
assessments of his demeanor.
   On October 22 and 23, 2012, Walters interviewed six such
employees. Five of them reported similar types of behavior
from Lauth. They described him as unprofessional, conde-
scending, and non-communicative. The sixth employee said
she did not have any problems with Lauth, but knew that
others did.
    After speaking with these employees, Walters met with
Sturgeon and recommended that Covance terminate Lauth’s
employment, based on continued performance deficiencies
in violation of the obligations of his PIP. Sturgeon and Cov-
ance’s legal department agreed with the recommendation. On
October 25, 2012, Walters and Sturgeon met with Lauth and
terminated his employment.
12                                                    No. 16-2939

    Based on his September 2012 EEOC charge, Lauth filed this
suit against Covance, alleging age discrimination and retalia-
tion under the Age Discrimination in Employment Act, 29
U.S.C. § 621 et seq. Covance moved for summary judgment,
arguing that Lauth had failed to establish a dispute of material
fact as to Covance’s motives for his termination. On June 14,
2016, the district court granted summary judgment on both
claims in favor of Covance. Lauth timely appealed.
                       II. DISCUSSION
    We review a grant of summary judgment de novo. Whitaker,
849 F.3d at 684 (citation omitted). “Summary judgment is
appropriate and the moving party is entitled to judgment as a
matter of law ‘where there is no genuine dispute as to any
material fact.’” Riley v. Elkhart Cmty. Sch., 829 F.3d 886, 891 (7th
Cir. 2016) (quoting Fed. R. Civ. P. 56(a)).
     A. Age Discrimination Claim
    Lauth’s first claim is that his termination constituted
discrimination in violation of 29 U.S.C. § 623(a)(1). The parties
agree that Lauth meets the threshold requirements to bring
such a claim, in that he was discharged and was over the age
of forty at the time. See id. §§ 623 and 631. Therefore, the only
remaining question for purposes of summary judgment is
whether there is a triable issue of fact as to whether Covance
terminated Lauth because of his age.
   We recently discarded the distinction between direct and
indirect methods of proof in employment discrimination cases,
and clarified that all evidence must be evaluated as a whole.
Ortiz v. Werner Enters., Inc., 834 F.3d 760, 765–66 (7th Cir. 2016).
No. 16-2939                                                      13

Thus, the proper inquiry before us now is whether a reasonable
jury could determine, based on all of the record evidence, that
Lauth’s age was the cause of his termination. See David v. Bd. of
Trs. of Cmty. Coll. Dist. No. 508, 846 F.3d 216, 225 (7th Cir. 2017)
(After Ortiz, “the question remains: has the non-moving party
produced sufficient evidence to support a jury verdict of
intentional discrimination?”); see also Ripberger v. Corizon, Inc.,
773 F.3d 871, 880 (7th Cir. 2014) (ADEA claim requires showing
that age was but-for cause of discharge).
    Lauth does not cite any specific examples of conduct or
statements by any of his superiors that could raise the infer-
ence of a discriminatory motive, in and of themselves. Instead,
Lauth argues that circumstantial evidence shows that his age,
rather than any issues with his performance, was the cause of
his termination. He contends that he performed his job
satisfactorily throughout his employment, and that Ellsworth
was younger, similarly situated, and treated more favorably.
The record, however, belies both contentions.
    First, it is clear that, at the time of his termination, Lauth’s
supervisors did not believe he was performing his job ade-
quately. Lauth’s performance reviews demonstrate that from
the time he started at Covance in 2006, his supervisors found
his demeanor and communication style problematic. Lauth
makes much of the fact that he received a “Meets Expectations”
rating, or better, on all of his year-end PMDs. In each of those
PMDs, however, Lauth’s communication was described as an
issue that he needed to remedy. In Lauth’s 2011 mid-year and
year-end PMDs, Snyder wrote that Lauth’s management
approach was no longer acceptable and that he needed to make
obvious improvements in his interactions with other staff and
14                                                No. 16-2939

leadership. This was followed by Marsh’s written warning
in July 2012, which was prompted by his “argumentative
and insubordinate” discussion with Walters. Lauth received
another negative mid-year PMD in 2012, in addition to a PIP,
which was due to his “repeated inappropriate and unprofes-
sional feedback.” Despite these indications that his conduct
was unacceptable, Lauth then took it upon himself to investi-
gate the incident between Ellsworth and Carter, even after
Walters told him she was handling it. Walters and Grubb both
told Lauth this was not appropriate behavior. Finally, October
2012 brought the string of complaints from Lauth’s shift
employees. That history clearly demonstrates that Covance
was not satisfied with Lauth’s job performance.
    Lauth’s only arguments against that assessment are that his
supervisors’ concerns were misplaced and that those who
complained about him did not have a basis to do so. Aside
from his contentions that he did not have the communication
issues that his supervisors saw as problematic, he offers no
evidence to suggest that Covance’s concerns were pretextual.
However, Lauth’s belief that he was performing his job
adequately is not relevant to the question of whether Covance
believed it had a legitimate, non-discriminatory basis to
terminate him. See Simpson v. Beaver Dam Cmty. Hosp., Inc., 780
F.3d 784, 795 (7th Cir. 2015) (“The question is not whether the
employer’s stated reason was inaccurate or unfair, but whether
the employer honestly believed the reasons it has offered to
explain its decision.”) (citation, quotation marks, and alter-
ations omitted). Lauth does not cite any evidence that would
allow for a reasonable inference that Covance did not have
honest concerns about his communication style and behavior.
No. 16-2939                                                   15

    The record also defeats Lauth’s argument that he and
Ellsworth were similarly situated and that Ellsworth was
treated more favorably. “[A]n employee is similarly situated to
a plaintiff if the two employees deal with the same supervisor,
are subject to the same standards, and have engaged in similar
conduct without such differentiating or mitigating circum-
stances as would distinguish their employer’s treatment of
them.” Hanners v. Trent, 674 F.3d 683, 692–93 (7th Cir. 2012)
(citation omitted). The parties agree that Lauth and Ellsworth
had the same supervisor and were subject to the same behavior
standards. The question, then, is whether they engaged in
similar conduct that was treated differently.
    On this score, Lauth falls woefully short. In each of Lauth’s
PMDs, from 2006 through 2012, his supervisor indicated that
his communication style was problematic. There is no indica-
tion in the record that Ellsworth received similar feedback over
such a long period of time. Moreover, Snyder, Grubb, Walters,
and Marsh all testified that Ellsworth and Lauth responded
differently to concerns about their behavior. Ellsworth demon-
strated a willingness to correct the problems, while Lauth
continuously pushed back on and disagreed with his supervi-
sors’ assessments. When Ellsworth’s behavior did become a
problem in 2011, he was placed on a PIP, which he completed
to Covance’s satisfaction in January 2012. Lauth was placed on
a PIP in August 2012, but continued to exhibit behavior his
supervisors found problematic. Walters also received numer-
ous complaints from other employees regarding Lauth’s
behavior, while he was on the PIP. The record does not contain
any examples of similar complaints regarding Ellsworth, aside
from those Lauth made himself. Based on the discrepancies in
16                                                  No. 16-2939

their problematic behavior, as well as their responses to
requests to remedy that behavior, Lauth is unable to demon-
strate that he and Ellsworth were similarly situated.
    Lauth has failed to point to any evidence, other than his
belief that Covance’s assessments of his workplace behavior
were mistaken, from which a jury could infer that Covance
terminated him because of his age. Therefore, his age discrimi-
nation claim fails.
     B. Retaliation Claim
     Lauth also claims that Covance disciplined and terminated
him as retaliation for making his AlertLine complaint and for
filing charges of discrimination with the EEOC. To survive
summary judgment on his retaliation claim, Lauth must
establish that (1) he engaged in a protected activity; (2) he
suffered an adverse employment action; and (3) there is a
causal link between the protected activity and the adverse
action. Hutt v. AbbVie Prods. LLC, 757 F.3d 687, 693 (7th Cir.
2014) (citation omitted). As with the discrimination claim, we
no longer recognize a distinction between direct or indirect
evidence, and instead consider all of the record evidence to
determine whether a causal link exists. See Ortiz, 834 F.3d at
765–66.
    Lauth’s EEOC charges were protected activities for pur-
poses of his retaliation claim. Smith, 674 F.3d at 658. His
AlertLine complaint, however, does not qualify as a protected
activity because it explicitly disclaimed his age as the underly-
ing basis for the harassment of which he complained. Id.
(“General complaints … do not constitute protected activity
under the ADEA because they do not include objections to
No. 16-2939                                                     17

discrimination based on … age.”). Therefore, we will analyze
his retaliation claim only as it relates to the filing of his EEOC
charges.
    Lauth’s argument mistakenly assumes that his negative
performance reviews, Marsh’s written warning in 2012, and his
PIP in 2012, all constitute adverse employment actions. These
are not adverse actions, however, because Lauth cannot show
that they resulted in a “quantitative or qualitative change in
the terms or conditions of employment.” Haywood v. Lucent
Techs., Inc., 323 F.3d 524, 532 (7th Cir. 2003), overruled on other
grounds by Ortiz, 834 F.3d at 765; see also Lagenbach v. Wal-Mart
Stores, Inc., 761 F.3d 792, 799 (7th Cir. 2014) (negative perfor-
mance reviews and PIPs are not adverse employment actions)
(citations omitted). Lauth’s discharge, on the other hand,
clearly constitutes an adverse employment action.
    Thus, the only question remaining is whether there is a
causal link between Lauth’s filing of the EEOC charges and his
termination. Lauth fails to point to evidence, circumstantial or
otherwise, from which a jury could infer such a link. Instead,
as with his age discrimination claim, his argument is simply
that because, in his view, his supervisors’ concerns were
mistaken or misplaced, the actions they took must have been
retaliatory. He contends, for example, the complaints made
against him in October 2012 all involved the proper exercise
of his supervisory authority, and that Covance accepted the
other employees’ versions of events uncritically and without
investigation. He also takes issue with the reasons he was
given a written warning and placed on the PIP, and attempts
to explain that he was justified in performing his own investi-
gation of the incident between Ellsworth and Carter.
18                                                      No. 16-2939

    As we have already said, however, judgments regarding
the fairness of a particular action or the accuracy of an em-
ployer’s belief about an employee’s job performance have no
place in determining whether the employer acted based on an
improper motive. Simpson, 780 F.3d at 795. Whether Lauth
agreed with the basis for the repeated comments regarding his
communication style, the basis for the warning and the PIP, or
the substance of the employees’ complaints is irrelevant to our
inquiry. The only question that matters is whether Covance
actually believed it had a legitimate basis to terminate Lauth.
See id.
    Lauth has not cited any evidence, other than his own
speculation, that might indicate Covance used the litany of
complaints and the documented history of his communication
issues as a cover for its retaliatory motive. That speculation is
insufficient to raise a question of fact, particularly in light of the
Covance’s consistent, longstanding, and progressive concerns
about his behavior. See Argyropolous v. City of Alton, 539 F.3d
724, 737 (7th Cir. 2008) (mere speculation that employer lied to
conceal true motives insufficient to withstand summary
judgment).
     C. Bill of Costs
    Lauth raises one final point, unrelated to the substance of
his claims. On June 21, 2016, upon motion by Covance, the
district court clerk entered a bill of costs, awarding $7,506.87
in costs to Covance. That amount included a $2,000 “deposition
fee” from Dr. Malcolm Cohen, Covance’s expert witness who
was deposed at Lauth’s request. The remainder was made up
No. 16-2939                                                      19

of the cost of deposition transcripts Covance used for its
motion for summary judgment.
    Lauth did not challenge the bill of costs in the district court.
On appeal, however, Lauth argues that the inclusion of
the $2,000 was error because certain expert fees are not
recoverable under 28 U.S.C. § 1920, which sets forth the taxable
costs that may be entered in a bill of costs. We review an award
of costs for an abuse of discretion. O’Regan v. Arbitration
Forums, Inc., 246 F.3d 975, 989 (7th Cir. 2001). “The award of
costs is the type of discretionary ruling to which we give
virtually complete deference.” Id. (citation and quotation
marks omitted).
    Federal Rule of Civil Procedure 54(d)(1) provides that costs
may be awarded to the prevailing party. The rule also sets
forth the procedure for awarding and challenging such costs:
“The clerk may tax costs on 14 days’ notice. On motion served
within the next 7 days, the court may review the clerk’s
action.” Fed. R. Civ. P. 54(d)(1). We have held that a party who
fails to challenge the imposition of costs within Rule 54's time
limit has waived any objection to those costs. See Cooper v. Eagle
River Mem’l Hosp., Inc., 270 F.3d 456, 464 (7th Cir. 2001) (citing
Rowe v. Maremont Corp., 850 F.2d 1226, 1244 (7th Cir. 1988)).
    Covance has not argued on appeal that Lauth waived his
objection to the deposition fee, but we can invoke waiver
sua sponte, see United States v. Gimbel, 782 F.2d 89, 91 n.5 (7th
Cir. 2001), and we elect to do so here. The district court clerk
entered the bill of costs on June 21, 2016. By failing to file a
motion challenging any of those costs on or before June 28,
2016, Lauth waived such a challenge. See Cooper, 270 F.3d at
20                                                 No. 16-2939

464. A finding of waiver is further supported by Lauth’s
undeveloped argument on appeal, the entirety of which
consists of a single paragraph at the end of his opening brief.
See Campania Mgmt. Co. v. Rooks, Pitts, & Poust, 290 F.3d 843,
852 n.6 (7th Cir. 2002) (“Perfunctory and undeveloped argum-
ents are waived … .”). Lauth did not give the district court the
opportunity to address the issue within the time prescribed by
Rule 54, and we are, therefore, barred from reviewing it.
                     III. CONCLUSION
    The district court’s order granting Covance’s motion for
summary judgment and the entry of the bill of costs are
affirmed.
