United States Court of Appeals
         FOR THE DISTRICT OF COLUMBIA CIRCUIT



Argued April 2, 2018              Decided September 4, 2018

                        No. 17-1151

        TEACHERS COLLEGE, COLUMBIA UNIVERSITY,
                     PETITIONER

                             v.

           NATIONAL LABOR RELATIONS BOARD,
                     RESPONDENT

LOCAL 2110, TECHNICAL, OFFICE AND PROFESSIONAL UNION,
           UNITED AUTO WORKERS AFL-CIO,
                    INTERVENOR


                 Consolidated with 17-1184


       On Petition for Review and Cross-Application
               for Enforcement of an Order of
            the National Labor Relations Board


    Matthew J. Frankel argued the cause for petitioner. With
him on the briefs were Kenneth J. Nichols and Tara E. Daub.

    David Casserly, Attorney, National Labor Relations Board,
argued the cause for respondent. With him on the brief were
Peter B. Robb, General Counsel, John H. Ferguson, Associate
General Counsel, Linda Dreeben, Deputy Associate General
                                 2

Counsel, and Ruth E. Burdick, Deputy Assistant General
Counsel.

    Before: GARLAND, Chief Judge, and EDWARDS and
SILBERMAN, Senior Circuit Judges.

    Opinion for the Court filed by Chief Judge GARLAND.

    Concurring opinion filed by Senior Circuit Judge
SILBERMAN.

     GARLAND, Chief Judge: Teachers College, an educational
institution affiliated with Columbia University, petitions for
review of a decision of the National Labor Relations Board.
That decision affirmed an administrative law judge’s conclusion
that the College violated the National Labor Relations Act by
refusing to provide information requested by a union
representing the College’s secretarial and clerical employees.
The College contends that the union failed to demonstrate the
relevance of the requested information. As we explain below,
however, substantial evidence supports the Board’s finding that
the information was relevant and that the College was obligated
to provide it. We therefore deny the petition for review and
grant the Board’s cross-application for enforcement.

                                 I

     Article I of the collective bargaining agreement (CBA)
between the College and Local 2110, United Auto Workers,
recognizes the union as “the exclusive bargaining agent for . . .
all on campus full-time and part-time . . . secretarial and clerical
employees.” CBA art. I, ¶ 1 (J.A. 157). Since 2012, the union
has suspected the College of violating the CBA by transferring
work reserved to the bargaining unit to non-unit College
employees. See Email from Jennifer Myers, Local 2110, to
                                3

Randy Glazer, Teachers College (June 13, 2012) (J.A. 397);
Teachers College, 365 N.L.R.B. No. 86, at 2 (May 31, 2017)
(ALJ Opinion) (J.A. 463). After communicating these
suspicions during contract negotiations in the spring of 2012, the
union filed a formal grievance with the College. See Email from
Myers to Glazer (Apr. 2, 2012) (J.A. 399); ALJ Opinion, 365
N.L.R.B. No. 86, at 2 (J.A. 463).

     In its grievance, the union requested a list of “all non-unit
part-time, casual, hourly, temporary and internship” employees
and, for each employee, his or her “name, job title/classification,
department, rate of pay, work schedule, actual number of hours
worked per week,” and starting and ending dates. See Email
from Myers to Glazer (Apr. 2, 2012) (J.A. 399). After a few
weeks of back-and-forth, the College advised the union that it
was “in the process of gathering items and w[ould] respond to
[the union’s] requests when that process [wa]s completed.”
Opinion & Award, Local 2110, UAW v. Teachers College, at 3
(Mar. 25, 2015) (March 2015 Arbitrator Opinion) (J.A. 188).
But the College later changed course, saying it believed the
union was requesting this information only “to support a charge
of unlawful conduct.” Email from Glazer to Myers (Sept. 7,
2012) (J.A. 400). As such, the College asserted that it “ha[d] no
obligation to provide [the requested] information.” Id.

     The College acknowledged that, “if [the union] believe[s]
that particular work has been improperly transferred out of the
unit to a non-unit employee in violation of the CBA, this could
be subject to the grievance and arbitration procedure.” Id. And
it further acknowledged that, “if a unit position is formally
assigned a significant responsibility . . . , that position should
normally maintain that responsibility unless there is good cause
for it to not be the case.” Email from Glazer to Myers, at 2
(Dec. 4, 2012) (J.A. 403). Claiming that the CBA permitted the
shared work responsibilities about which the union complained,
                                4

however, the College denied the grievance in December 2012.
Id.

     The union took the matter to arbitration. In January 2015,
the arbitrator concluded that the union’s grievance was
arbitrable under the CBA, and that he “ha[d] the authority to
determine whether non-bargaining unit employees are
performing unit work, and/or whether the College has
transferred unit work to non-unit employees, and to fashion an
appropriate remedy.” Opinion & Award, Local 2110, UAW v.
Teachers College, at 12 (Jan. 21, 2015) (January 2015 Arbitrator
Opinion) (J.A. 185). The arbitrator ordered the parties to agree
on what information the College would provide the union to
facilitate further proceedings. March 2015 Arbitrator Opinion,
at 5 (J.A. 189).

     Following the arbitrator’s order, the union’s counsel sent
the College’s counsel a more targeted request for information
regarding non-unit positions it suspected were performing unit
work. See Letter from Alek Felstiner, Local 2110, to Tara Daub,
Teachers College, at 1 (Apr. 13, 2015) (J.A. 194). The College
again refused to provide any information, saying that it would
not do so unless the union identified for each position “(i) the
unit work allegedly transferred to such employees; (ii) the basis
for the Union’s belief that unit work has been transferred to such
employees; and (iii) the alleged connection between the unit
work and the information requested.” Letter from Daub to
Felstiner, at 4 (Apr. 17, 2015) (J.A. 201).

     The union then made two further efforts to address those
topics. First, in response to the College’s request that the
arbitrator dismiss the grievance, the union wrote a letter
explaining at length why it believed the information requested
was relevant to determining whether the College had
impermissibly transferred work outside the unit. See Letter from
                                5

Felstiner to Richard Adelman, Arbitrator, at 3-5 (Sept. 10, 2015)
(J.A. 337-39).

    Second, after the arbitrator rejected the College’s request to
dismiss the grievance, see Opinion & Award, Local 2110, UAW
v. Teachers College, at 5 (Sept. 28, 2015) (September 2015
Arbitrator Opinion) (J.A. 350), the union updated its request yet
again and in more detail. As the administrative law judge (ALJ)
summarized:

         [T]he Union had its members canvass the College, and
         review documentary and other evidence in their
         possession regarding what positions were performing
         unit work. Along with the Union’s attorney, they
         compiled a list of nonunit positions that, in the Union’s
         belief, performed unit work, going building by
         building, department by department, and floor by floor.
         The Union’s attorney gathered the information they
         knew about each position, including the title,
         department, and history of the position, and created a
         chart of 34 nonunit positions. Along with a list of the
         position titles, the chart included the department for
         each position, and a short “comments” section setting
         forth the basis for the Union’s belief and/or a
         description of the specific position in question.

ALJ Opinion, 365 N.L.R.B. No. 86, at 3 (citation omitted) (J.A.
464).

     On October 22, 2015, the union emailed this chart to the
College, asking the College to provide the information related
to the listed positions. The email stated that the union had
developed the chart by using job postings, information about
assignment changes from unit employees, and unit employees’
observations of the job functions non-unit employees were
                                6

performing. See id. The College once again accused the union
of seeking the information for improper purposes and refused to
budge unless the union further identified the unit work at issue.
See Letter from Daub to Felstiner, at 4-5 (Oct. 28, 2015) (J.A.
366-67).

     Three weeks later, the union filed an unfair labor practice
charge with the National Labor Relations Board (NLRB). After
a hearing, an ALJ concluded that the College violated section
8(a)(1) and (5) of the National Labor Relations Act (NLRA), 29
U.S.C. § 158(a)(1), (5), when it refused to provide the union
with the information it had requested on October 22, 2015. ALJ
Opinion, 365 N.L.R.B. No. 86, at 6 (J.A. 467).

     The ALJ found that, by the time of its October 2015
request, the union “had established and demonstrated to the
College both the relevance of the requested information and the
existence of evidence that gave rise to the Union’s reasonable
belief in the relevance of that information.” Id. at 4 (J.A. 465).
The ALJ also concluded that the College had no valid defense
because it failed to establish that the union’s information request
was made in bad faith as a discovery substitute for intended
Board proceedings. Id. at 5 (J.A. 466). Finally, the judge held
that the union’s request was not overly broad or unduly
burdensome because, inter alia, its request was “specifically
targeted” to the positions identified, and the information was
“the type of information that would either directly assist the
Union in the arbitration or assist them in identifying further
evidence to present to the arbitrator.” Id.

    On May 31, 2017, the NLRB affirmed the ALJ’s decision.
See Teachers College, 365 N.L.R.B. No. 86, at 1 (Board
Decision) (J.A. 462). The College now petitions for review, and
the Board cross-applies for enforcement of its order.
                                7

                                II

     The College challenges the Board’s determination that it
violated section 8(a)(5) and (1) of the NLRA by refusing to
produce the information the union requested.

     Section 8(a)(5) imposes on an employer the “duty to
bargain collectively.” Detroit Edison Co. v. NLRB, 440 U.S.
301, 303 (1979). That duty “has long been acknowledged to
include a duty to supply a union with requested information that
will enable [the union] to negotiate effectively and to perform
properly its other duties as bargaining representative.” Oil,
Chem. & Atomic Workers Local Union No. 6-418 v. NLRB, 711
F.2d 348, 358 (D.C. Cir. 1983) (internal quotation marks
omitted). “Because a union’s other duties include the duty to
see to it that an employer meets its [collective bargaining
agreement] obligations, the employer’s duty to furnish
information extends to data requested in order properly to
administer and police a collective bargaining agreement.” N.Y.
& Presbyterian Hosp. v. NLRB, 649 F.3d 723, 729 (D.C. Cir.
2011) (citation and internal quotation marks omitted).

     “[T]he duty imposed by section 8(a)(5) is subject to a
minimum standard of relevance: ‘The union’s need and the
employer’s duty depend, in all cases, on the probability that the
desired information [is] relevant, and that it [will] be of use to
the union in carrying out its statutory duties and
responsibilities.’” Id. at 729-30 (quoting Oil, Chem. & Atomic
Workers, 711 F.2d at 359). The requisite showing of relevance
depends on whether the union is requesting information about
employees who are part of the bargaining unit or outside it.
“For information about employees in the bargaining unit, it is
presumed that the requested information is relevant . . . , and the
employer must provide the information unless it can show the
information is irrelevant.” U.S. Testing Co. v. NLRB, 160 F.3d
                                 8

14, 19 (D.C. Cir. 1998). With respect to employees outside the
bargaining unit, “the burden is on the union to demonstrate the
relevance of [the requested] information.” Id.; see N.Y. &
Presbyterian Hosp., 649 F.3d at 730.

     In this case, the union sought information regarding
employees outside the bargaining unit in order to determine
whether the employer was improperly transferring unit work to
them. Accordingly, the burden was on the union to demonstrate
the relevance of the information. Thus, a “bare assertion that it
needs information” would be insufficient; the union needed to
“explain to the employer why the information is relevant.” 649
F.3d at 730. “Nevertheless,” as we explained in Presbyterian
Hospital, “the threshold for relevance is low. In particular, the
union need not demonstrate the existence of some particular
controversy or the need to dispose of some recognized problem.
Rather, we apply a discovery-type standard, under which [t]he
fact that the information is of probable or potential relevance is
sufficient to give rise to an obligation” to provide it. Id.
(citations and internal quotation marks omitted); see NLRB v.
Acme Indus. Co., 385 U.S. 432, 437 & n.6 (1967); Brewers &
Maltsters, Local Union No. 6 v. NLRB, 414 F.3d 36, 45 (D.C.
Cir. 2005); Oil, Chem. & Atomic Workers, 711 F.2d at 359.

     The Board’s factual findings are conclusive if supported by
“substantial evidence on the record considered as a whole.” 29
U.S.C. § 160(e). “Under this standard, ‘the Board is to be
reversed only when the record is so compelling that no
reasonable factfinder could fail to find to the contrary.’” Pub.
Serv. Co. v. NLRB, 843 F.3d 999, 1004 (D.C. Cir. 2016)
(quoting Fort Dearborn Co. v. NLRB, 827 F.3d 1067, 1072
(D.C. Cir. 2016)). And, “[b]ecause Congress has determined
that the Board has the primary responsibility of marking out the
scope . . . of the statutory duty to bargain, great deference is due
to the Board’s determinations of the scope of an employer’s
                                9

obligation to provide requested information to a union,” as that
obligation “derive[s] from the statutory duty to bargain.” Id.
(internal quotation marks omitted).

                                A

     The College’s principal contention is that substantial
evidence does not support the Board’s finding that the union met
its burden to demonstrate the relevance of the information it
sought. We disagree.

     1. As just noted, the courts and the Board apply a
“discovery-type” standard, under which “[t]he fact that the
information is of probable or potential relevance is sufficient to
give rise to an obligation” to provide it. N.Y. & Presbyterian
Hosp., 649 F.3d at 730 (internal quotation marks omitted); see,
e.g., Acme, 385 U.S. at 437 & n.6. All that is required is “a
reasonable belief, supported by objective evidence, that the
requested information is relevant.” Disneyland Park, 350
N.L.R.B. 1256, 1257-58 (2007). Under this standard, substantial
evidence amply supports the ALJ’s finding that, “by the time of
its October 22, 2015 information request, the Union had
established and demonstrated to the College both the relevance
of the requested information and the existence of evidence that
gave rise to the Union’s reasonable belief in the relevance of
that information.” ALJ Opinion, 365 N.L.R.B. No. 86, at 4 (J.A.
465).

     As the ALJ explained, in early 2015, “the arbitrator
determined that he had the authority to determine whether
nonbargaining unit employees were performing bargaining unit
work, and/or whether the College transferred unit work to non-
unit employees, and to fashion an appropriate remedy.” Id.
Thereafter, “[r]elying upon information received from union
members [who] canvass[ed] the College in October 2015, along
                                10

with job postings and other documents in the Union’s
possession, the Union identified 34 nonunit positions it believed
were performing bargaining unit work.” Id. It then compiled
this information into a chart that listed, for each such position,
“to the best of its knowledge, the position name and department,
and included a ‘comment’ section describing the specific
position in question, or identifying the basis of the Union’s
belief that the position was performing unit work.” Id.

     On October 22, 2015, the union emailed the chart to the
College. Email from Felstiner to Daub (Oct. 22, 2015) (J.A.
359) (attaching List of Positions Chart (J.A. 360-61)). The
email stated the union’s belief “that the College has improperly
transferred bargaining unit work to employees in these
positions.” Id. The email further advised the College that, as
recounted above, the “comments” column of the chart included
“a brief note reflecting the basis for the Union’s belief that the
College improperly transferred unit work to the position(s) in
question.” Id. And it explained to the College how the union
developed the information. Id.

     The chart, and the work the union undertook to construct it,
provide sufficient support for the ALJ’s finding that the union
had, and presented to the College, a reasonable belief that unit
work was being performed outside the unit -- a concern that was
directly relevant to its grievance. See ALJ Opinion, 365
N.L.R.B. No. 86, at 4 (J.A. 465). As we have noted, the CBA
recognized the union as “the exclusive bargaining agent for . . .
all on campus full-time and part-time . . . secretarial and clerical
employees.” CBA art. I, ¶ 1 (J.A. 157). It further defined
“secretarial and clerical employees” as

         including clerks, account clerks, secretaries,
         receptionist-typists, clerk-typists, assistant supervisors
         in the Word Processing Center, correspondence clerks,
                                11

         postal clerks, library assistants, personnel assistants,
         duplicating equipment operators, electronic data
         processing machine operators, bookkeeping machine
         operators, bookkeeping machine operator supervisors,
         key-punch operators, key-punch operator supervisors,
         audiovisual technicians, student financial aid
         counselors, cashiers, and telephone operators . . . .

Id. And the chart showed -- based on canvassing, job postings,
and other documents -- numerous non-unit positions that
appeared, at least on their face, to involve the bargaining unit
work of “secretarial and clerical employees.” Those included:
five “secretary” positions and four positions previously filled by
secretaries; three “front desk” positions and a fourth with “front
desk” duties included in its job description, positions that were
traditionally and reasonably associated with receptionist or
secretarial work; two interim bookkeeping “clerk” positions; as
well as other positions that reasonably appeared to be included
within the definition of “secretarial and clerical employees”
quoted above. See List of Positions Chart (J.A. 360-61).

      The union’s October 22 email asked the College to provide
the following information for each of the 34 positions listed in
the chart: (1) the title of the position; (2) the name or names of
employee(s) filling the position; (3) the position type; (4) the
department; (5) the regular schedule for the position; (6) the rate
of pay; and (7) the current or past job descriptions. Email from
Felstiner to Daub (Oct. 22, 2015) (J.A. 359). It is obvious to us,
as it was to the ALJ, that this kind of information was relevant
for processing the grievance and preparing for arbitration on the
issue, both of which are central to the union’s “carrying out its
statutory duties and responsibilities,” Acme, 385 U.S. at 437.
See ALJ Opinion, 365 N.L.R.B. No. 86, at 4 (J.A. 465).
                               12

     Indeed, in Presbyterian Hospital, we said as much
regarding a union’s request for information including non-unit
“nurse practitioners’ names . . . ; the departments or units where
the nurse practitioners are assigned to work; their job duties and
their start dates at the hospital.” 649 F.3d at 727 (internal
quotation marks omitted). “There can be little dispute,” we said,
that the information request “is relevant to the question whether
non-bargaining unit [nurse practitioners] are performing
bargaining unit work,” and so “the [h]ospital was obligated to
provide [the information].” Id. at 730. The same is true here.

     2. We find unpersuasive the College’s efforts to downplay
the sufficiency of the union’s showing.

     The College argues that the union did not possess “objective
evidence” of the relevance of its information requests “at the
time of its request[s].” Reply Br. 1 (quoting Pub. Serv. Co., 843
F.3d at 1005; N.Y. & Presbyterian Hosp., 649 F.3d at 731). It
charges that “Union counsel testified that he had no knowledge
or belief, at the time he prepared and sent his October 2015 chart
to Teachers College, as to what job duties the non-unit positions
listed in the chart were performing or whether the union
believed that any duties they performed were ‘unit work.’”
College Br. 27 (citing ALJ Hearing Tr. 62-65, 125-26 (J.A. 42-
45, 86-87)). But this contention mischaracterizes the testimony:
union counsel said only that he could not “speak to the Union’s
knowledge as of November 20, 2014,” ALJ Hearing Tr. 65
(emphasis added) (J.A. 45) -- nearly a year before the October
2015 information request at issue here.

     The parties agree that a union seeking information that is
not presumptively relevant (as here) must “explain why the
information is relevant” and must be able to support that
explanation “with objective evidence.” College Br. 26-27;
NLRB Br. 18-19; see N.Y. & Presbyterian Hosp., 649 F.3d at
                                   13

730; Disneyland Park, 350 N.L.R.B. at 1258. The College
further contends, however, that a union must not only explain
relevance and possess objective evidence, but must also present
that evidence to the employer at the time of its request. The
NLRB disagrees.1 Regardless of whether the College is correct
on this front, the union has satisfied that requirement in this
case. As of the date of the request, the union did have and did
present the College with objective evidence: the member
canvass and the postings to which it referred in its October 2015
email and chart. See ALJ Opinion, 365 N.L.R.B. No. 86, at 3
(J.A. 464). That evidence was sufficient.2




     1
       See Cannelton Indus., 339 N.L.R.B. 996, 997 (2003) (“A union
cannot meet its burden based on a mere suspicion . . . ; it must have an
objective, factual basis for [its belief] . . . . Under current Board law,
however, the union is not obligated to disclose those facts to the
employer at the time of the information request. Rather, it is sufficient
that the General Counsel demonstrate at the hearing that the union
had, at the relevant time, a reasonable belief.”); accord DirectSat USA,
LLC, 366 N.L.R.B. No. 40, at 4 (Mar. 20, 2018); Piggly Wiggly
Midwest, LLC, 357 N.L.R.B. 2344, 2344 (2012).
     2
       See Walter N. Yoder & Sons, Inc. v. NLRB, 754 F.2d 531, 536
(4th Cir. 1985) (crediting union president’s testimony that another
union official “reported to [him] that Yoder employees had told” the
official about integrated operations with an alleged non-union
alter-ego company); Castle Hill Health Care Ctr., 355 N.L.R.B. 1156,
1156, 1181 (2010) (affirming ALJ’s conclusion that an information
request, generally citing “anecdotal information” from members,
relied on “hearsay evidence . . . sufficient to support an information
request”); Magnet Coal, Inc., 307 N.L.R.B. 444, 444 n.3, 448 (1992)
(crediting union president’s testimony that he “had heard from
employees . . . that the Company [and its alleged non-union alter-ego]
had interchanged equipment”), enforced, 8 F.3d 71 (D.C. Cir. 1993).
                                14

     The College also complains that the chart proffered by the
union was too “conclusory.” College Br. 44; see id. at 26-27.
The chart, the College says, “provided only a list of 34 vaguely
identified non-unit positions.” Id. at 33. Again, we disagree.
For each of the 34 positions, the union named the position and
the department in which it was located. The chart’s comments
section added additional information, where available to the
union, including the position’s physical location, its history, and
whether it was listed in the College’s job postings.

     The College says that many of the 34 positions listed in the
chart used imprecise or inaccurate job titles. But to the extent
the union’s proffer reflected incomplete information about the
identified work transfers, that lack of knowledge was precisely
the reason for the information request and does not, as the
College insists, prove that the union had “no good faith basis for
the grievance,” Id. at 8. See Crowley Marine Servs., Inc. v.
NLRB, 234 F.3d 1295, 1296 (D.C. Cir. 2000) (upholding the
Board’s finding of a violation where “the information was
sought and needed to enable the Union to make an informed
judgment” about pursuing contract violation remedies (internal
quotation marks omitted)); Shoppers Food Warehouse, 315
N.L.R.B. 258, 259 (1994) (“The Union was not required to show
that the information which triggered its request was accurate or
ultimately reliable, and a union’s information request may be
based on hearsay.”).

     Nor did the College, at any time, present any evidence
contradicting the union’s characterization of the referenced job
postings. Instead, it disclaimed any duty to look into the union’s
allegations before refusing its request, unless the union met the
College’s demands for greater specificity. See Recording of
Oral Arg. 28:03-29:20. Indeed, after repeated questioning at
oral argument, it was unclear whether the College had even
bothered to review the job postings mentioned in the October
                                15

2015 chart. As the Seventh Circuit said in NLRB v. George
Koch Sons, Inc.: “It was reasonable for the Union to rely on the
. . . observations of union officials, employee reports and records
in forming its reasonable suspicion that the [employer] was
diverting work to [a nonunion business the employer operated].
Therefore, considering that [the employer] did not present any
evidence contradicting the contents of these reports and
observations, [they] alone constitute substantial evidence . . .
that the Union reasonably suspected that [the employer] was
diverting work” in violation of the CBA. 950 F.2d 1324, 1333
(7th Cir. 1991) (citations omitted).

      The College also argues that the chart’s listings were
insufficient because Article I of the CBA “defines the
bargaining unit by titles, not by the type of work done by the
employees.” College Br. 30 n.5. This argument is somewhat
confusing, given that the College’s human resources director
acknowledged that allegations “that particular work has been
improperly transferred out of the unit . . . could be subject to the
grievance and arbitration procedure.” Email from Glazer to
Myers (Sept. 7, 2012) (J.A. 400). It also disregards those chart
listings that appear to describe positions by titles. The college
further argues that, even if the unit is defined by job duties
rather than titles, the cited duties are not exclusive to the unit
under the CBA.

    In any event, both of these arguments go to the merits of the
union’s grievance, upon which the Board does not pass in
assessing the relevance of the requested information. Bell Tel.
Labs., Inc., 317 N.L.R.B. 802, 803 (1995), enforced, 107 F.3d
862 (3d Cir. 1997). As the Supreme Court has explained:

         [W]hen it order[s] the employer to furnish the
         requested information to the union, the Board [is] not
         making a binding construction of the labor contract. It
                               16

         [is] only acting upon the probability that the desired
         information [is] relevant, and that it would be of use to
         the union in carrying out its statutory duties and
         responsibilities.     This discovery-type standard
         decide[s] nothing about the merits of the union’s
         contractual claims.

Acme, 385 U.S. at 437. The union was “not required to accept”
the College’s view of the CBA; it “was entitled to conduct its
own investigation and reach its own conclusions about the
applicability of the agreement.” Shoppers Food Warehouse, 315
N.L.R.B. at 259.

    3. Finally, the College maintains that, “[i]n its prior
decisions, the Board has made clear that this type of showing is
insufficient to establish relevance.” College Br. 34. The prior
decisions it cites are inapposite.

     The College cites Disneyland Park, in which the “Board
held that the agent’s ‘testimony did not explain how the
requested information would be relevant to support an arguable
violation of the contract,’ and thus could not ‘serve to establish
that the Union provided to the Respondent a sufficient factual
basis to establish relevance at the time the information request
was made.’” Id. at 36 (quoting Disneyland Park, 350 N.L.R.B.
at 1259). According to the College, the “exact same analysis
applies here.” Id. But it does not. In Disneyland Park, the
union requested information about non-unit employees to whom
the CBA expressly permitted the employer to subcontract work.
350 N.L.R.B. at 1258-59. Here, by contrast, the union points to
CBA language that is reasonably read as reserving to the unit the
work it believes was transferred. Indeed, the arbitrator
repeatedly stated that the union had presented an arbitrable
grievance regarding the transfer of unit work. See, e.g., January
2015 Arbitrator Opinion, at 12 (J.A. 185); September 2015
                                17

Arbitrator Opinion, at 4 (J.A. 349) (stating that “the Union may
be able to prove some contract violation”).

     The College also cites Postal Service, 310 N.L.R.B. 701
(1993), for the proposition that “vague, general reports” are
insufficient to show relevance. College Br. 35 (quoting Postal
Serv., 310 N.L.R.B. at 703). But in that case, the union’s basis
for requesting information about supervisors it thought might
have engaged in conduct similar to that for which an employee
was disciplined was “nothing more than that, at a union meeting,
employees had furnished supervisors’ names in response to an
appeal for the names of those who had had ‘prolonged
absences.’” Postal Serv., 310 N.L.R.B. at 703. Here, by
contrast, far from presenting the College with “vague, general
reports,” the union explained that its allegations were founded
on (1) a broad survey of unit members, who reported multiple
instances of improper work transfers, and (2) the College’s own
job postings. Union counsel Alek Felstiner testified before the
ALJ as follows:

         After the arbitrator’s decision [declining to dismiss the
         grievance], I met with Union members twice; groups of
         Union members at Teachers College, and they
         essentially canvassed the college and also surveyed
         documentary evidence, information that they had, in
         order to compile this list . . . and identify sort of
         building by building, floor by floor, department by
         department which positions the Union believed were
         performing unit work even though the positions were
         not in the unit.

ALJ Hearing Tr. 50 (J.A. 33).

    4. In sum, substantial evidence supports the NLRB’s
determination that the union had adequate and objective
                                18

evidence to support a reasonable belief that the requested
information was relevant to its pending grievance. What really
appears to underlie the College’s argument is an implied claim
that evidence satisfying more than a “discovery-type” standard
is required. But that is a claim our precedent rejects.

                                B

    The College challenges the Board’s decision on two
additional, but equally unpersuasive, grounds.

     First, the College contends that the record compels the
conclusion that the union requested the information in bad faith.
Under Board precedent, a union may not use an information
request, ostensibly made for purposes of policing a collective-
bargaining agreement, as a discovery device to pursue
proceedings before the NLRB. Union Tribune Publ’g Co., 307
N.L.R.B. 25, 26 (1992) (holding that, because Board procedures
do not include prehearing discovery, a party may not use an
information request to “impose a discovery requirement where
none otherwise exists”), enforced, 1 F.3d 486 (7th Cir. 1993);
WXON-TV, Inc., 289 N.L.R.B. 615, 617-18 (1988), enforced,
876 F.2d 105 (6th Cir. 1989). “An employer charged with
failing to provide requested information may argue as an
affirmative defense that the request was made in bad faith . . . .”
Monmouth Care Ctr. v. NLRB, 672 F.3d 1085, 1094 (D.C. Cir.
2012). “But the employer bears the burden of persuasion on that
defense,” id., and substantial evidence supports the NLRB’s
determination that the College failed to satisfy that burden.

     Much of the College’s argument on this point is a repetition
of its claim that the union had no reasonable basis for believing
that work had been transferred out of the unit, and hence no
basis for requesting the information as relevant. The “Union’s
inability to show an objective basis for the relevance of its
                                19

requests,” the College insists, “compels the conclusion that the
Union’s real objective is to prepare to use Board procedures for
organizing or accreting non-unit positions into the bargaining
unit.” College Br. 42. But we have rejected the contention that
the union was unable to show relevance, and thus that claimed
inability can hardly form the basis for an affirmative defense of
bad faith.

     The College also claims that the union openly “admitted its
intent was to either pursue [an unfair labor practice] charge
against Teachers College for ‘unlawful’ conduct or to file a unit
clarification petition to accrete non-unit positions into the
Union’s unit . . . , despite their express exclusion from the scope
of the CBA’s recognition clause.” Id. at 40. That assertion rests
on correspondence from three years before the October 2015
request, in which the union filed a grievance stating that the
College had improperly excluded positions from the unit. See
Email from Myers to Glazer (Apr. 2, 2012) (J.A. 399). In the
same correspondence chain, the union stated that the grievance
included the improper work transfers. See Email from Myers to
Glazer (June 13, 2012) (J.A. 397). Indeed, it pursued that work-
transfer grievance to arbitration. And, as the ALJ pointed out,
“at the time of the information request, there were no
outstanding charges or complaints pending before the Board.”
ALJ Opinion, 365 N.L.R.B. No. 86, at 5 (J.A. 466). To the
contrary, the only ongoing proceeding when the union made its
October 22, 2015 request was the arbitration. In that context,
the three-year-old correspondence does not satisfy the College’s
burden to show the union’s bad faith.

    Second, the College argues that, “even if, arguendo, the
Union demonstrated relevance with respect to certain positions,”
the union failed to establish the relevance of each type of
information it requested for each individual position in its
October 2015 chart. College Br. 43. As to this argument, our
                               20

analysis can be brief. In its exceptions below, the College did
not challenge or dispute the request as it applied to any specific
position. See College Br. in Supp. of Exceptions 20-21 (J.A.
446-47). We therefore may not consider such challenges now.
See 29 U.S.C. § 160(e); Monmouth, 672 F.3d at 1094.

                               III

    For the foregoing reasons, we deny the petition for review
and grant the Board’s cross-application for enforcement.

                                                     So ordered.
     SILBERMAN, Senior Circuit Judge, concurring: I am in full
agreement with the court’s reasoning. I write separately to
contest the reasonableness of the Board’s view expressed in
Piggly Wiggly Midwest, LLC, 357 N.L.R.B. 2344, 2344 (2012),
which we note in footnote 1 but upon which we do not rely. The
Board there said that although a union seeking information
concerning non-bargaining unit activities must have a factual
basis to support the relevance to the bargaining unit of that
information, it need not disclose those facts to the employer; it
is sufficient that the General Counsel present those facts to the
ALJ at an unfair labor practice hearing.

      I think that is a paradigmatic example of arbitrary and
capricious decision-making. An employer under Board law
must accommodate a union’s request for non-bargaining unit
information if it is relevant to bargaining unit concerns, but can
legitimately refuse if the union has no factual basis for asserting
that relevance. That decision must be made at the time of the
union’s request, and if the employer is wrong, it violates the law.
It seems to me to be absurd for the Board to hold that an
employer who is not faced with alleged facts supporting a
union’s claim of relevance at the time of the request – and
therefore apparently acting within the law – can be retroactively
determined to have violated the Act by virtue of factual evidence
first put on by the General Counsel at a hearing before an ALJ.
This seems to even raise an issue of due process.
