District 4, Communications Workers of America (cwa), Afl-Cio v. National Labor Relations Board

United States Court of Appeals
FOR THE DISTRICT OF COLUMBIA CIRCUIT
Submitted September 30, 2022 Decided February 14, 2023
No. 21-1188
D ISTRICT 4, COMMUNICATIONS WORKERS OF A MERICA
(CWA), AFL-CIO,
PETITIONER
v.
N ATIONAL LABOR RELATIONS BOARD ,
RESPONDENT
THRYV , I NC., FORMERLY KNOWN AS D EX MEDIA , I NC., D / B/A
D EX YP,
I NTERVENOR
On Petition for Review of an Order
of the National Labor Relations Board
Matthew R. Harris was on the briefs for petitioner.
Ruth E. Burdick, Deputy Associate General Counsel,
National Labor Relations Board, David Habenstreit, Assistant
General Counsel, Julie Broido, Supervisory Attorney, and
Gregoire Sauter, Attorney, were on the brief for respondent.

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David Zwisler was on the brief for intervenor Thryv, Inc.
in support of respondent.
Before: S RINIVASAN , Chief Judge, P ILLARD , Circuit
Judge, and SENTELLE , Senior Circuit Judge.
Opinion for the Court filed by Circuit Judge PILLARD .
Dissenting opinion filed by Senior Circuit Judge
SENTELLE .
PILLARD , Circuit Judge: We are asked to decide which of
two different retirement-benefit terms binds the parties to a
labor agreement. It is undisputed that, before the parties
arrived at the 2016 labor agreement at issue, the Company’s
benefit plan offered bargaining-unit employees a tax-
advantaged defined contribution plan under Internal Revenue
Code Section 401(k)—a “401(k)” for short. It is also common
ground that the predecessor collective bargaining agreement
did not mention any 401(k) benefit, whereas the new agreement
guarantees the employer will continue to provide a 401(k)
benefit. But the parties dispute which of two documents—with
different 401(k) terms—reflects their final and binding
agreement.
The Company asserted and the Board determined that the
binding agreement is the September 16, 2016, Memorandum of
Agreement, as hand signed by Company and Union bargaining
representatives. The Union asserts that a different contract
document, as typed up and circulated to the parties almost a
year later, is the one that binds. At first blush, it might seem
that the later document, finalized and circulated for the parties’
reference going forward, must be the authoritative agreement.
And the Company might appear to be on thin ice in objecting
to a more generous 401(k) term it concededly inserted into that

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finalized document—a term that the Union embraced and now
seeks to enforce. But, as the Board recognized, which of the
conflicting provisions applies turns on when the parties reached
final agreement: The retirement-benefit term they agreed to at
that time is the one that binds them.
The hand-signed 2016 Memorandum of Agreement states
that “[t]he Union and Employer collectively have reached
agreement and the predecessor agreement shall only be revised
as specifically set forth herein.” J.A. 709. That Agreement’s
401(k)-benefit term committed only that the labor agreement
would “acknowledge the provision of a 401(k) benefit.” J.A.
729. The version posted the following year is a revision of the
predecessor labor agreement, meant to incorporate the terms of
the 2016 Memorandum of Agreement. In contrast to the hand-
signed version, however, the revised contract document states
that the employer’s 401(k) matching rate will be “no less than
100% for each employee dollar contributed to individual
accounts up to 5% maximum contribution.” J.A. 371.
When the Company upgraded its retirement-benefit
offering in 2018, the Union brought the unfair labor practice
charge at issue here. The Union claimed that the Company
unilaterally modified the parties’ collective bargaining
agreement by “implementing a 401(k) contribution matching
structure other than that specifically negotiated and
memorialized in the CBA [Collective Bargaining
Agreement].” Charge Against Employer, Attachment A
(stating basis of charge), J.A. 3. The new, objected-to 401(k)
plan guaranteed up to 4.8 percent overall match—the same
overall match the Company had been providing, but structured
a bit more favorably to the beneficiaries than the previous plan
by front-loading the employer’s matching contribution. The
Union pointed to the “5% maximum contribution” language in
the revised contract document to assert that the new plan fell

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short. The Company responded that it had inserted that 5
percent term by mistake in the process of revising the
predecessor agreement to reflect the terms of the 2016
Memorandum of Agreement.
The Board dismissed the complaint, concluding that the
parties reached a final and binding labor contract as of
September 16, 2016, and that the difference between the 2016
Memorandum of Agreement and the 2017 contract revision
resulted from a drafting error. To identify when the parties
reached final agreement—and so which 401(k) term binds
them—the Board considered evidence of the parties’
bargaining history. The Board found that the parties reached
final agreement at the close of negotiations in September 2016,
when they signed the 2016 Memorandum of Agreement as the
exhaustive list of their agreed revisions to the 2013 predecessor
contract. During negotiations, the Board found, the Union had
proposed and the Company rejected a 6 percent and then a 5
percent 401(k) match. The decisive compromise leading to
agreement on the new contract was to expressly acknowledge
a 401(k) benefit, without commitment to any particular match.
The Company’s Board of Directors and the bargaining unit
members ratified the new contract in late 2016 based on the
2016 Memorandum of Agreement. The follow-up
communications between the Company’s and Union’s
representatives in 2017 were aimed at revising the 2013
contract’s text to reflect the terms of the Agreement they had
reached; the parties never purported to be negotiating
substantive terms during that ministerial process. In that
context, the Board permissibly determined that the hand-signed
2016 Memorandum of Agreement was final, binding, and
exhaustive, such that its retirement-benefit term governs.

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The Union seeks review here, arguing that the Board
misapplied its precedent, impermissibly considered parol
evidence of the parties’ bargaining history, and found facts
unsupported by substantial evidence. For the reasons that
follow, we deny the petition for review.
BACKGROUND
I. Facts
DexYP (the Company) publishes and sells the Yellow
Pages phone directory and other marketing tools. The
Company was known as YP Midwest Publishing until June
2017, when it was acquired by Dex Media Holdings, Inc. and
became DexYP. DexYP has a collective bargaining
relationship with the Communication Workers of America (the
Union), which represents a bargaining unit of staff associates,
service representatives, customer service specialists, and art
technicians. YP Midwest Publishing and the Union had
entered into a 2013 Collective Bargaining Agreement and a
2016 successor Collective Bargaining Agreement. When Dex
Media Holdings acquired the Company in 2017, the 2016
agreement remained in effect and the new management
committed to honoring all existing Collective Bargaining
Agreements and bargaining obligations.
The parties to the 2016 collective bargaining negotiations
used the terms of the 2013 Collective Bargaining Agreement
as the baseline from which they bargained. That predecessor
contract consisted of a main agreement with forty-one articles
and seven exhibits, plus thirty-seven side letters, a 2013
memorandum of agreement, and three appendices. Although
that pile of documents comprising the 2013 contract made no
mention of retirement benefits, the employer’s benefits plan at
the time included a 401(k) benefit for which the bargaining unit
employees were eligible. That 401(k) plan provided that, for

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employees who contributed up to 6 percent of their salary to a
401(k) account, the employer would match the employees’
contributions at 80 percent, i.e., contribute to an employee’s
retirement account an amount equal to 4.8 percent of the
employee’s salary.
In September 2016, the Company and the Union signed a
twenty-page Memorandum of Agreement memorializing the
various revisions they agreed to make to the 2013 contract. The
cover page of the Memorandum of Agreement stated: “The
Union and Employer collectively have reached agreement and
the predecessor agreement shall only be revised as specifically
set forth herein.” J.A. 709. The Memorandum of Agreement
reads like a to-do list of items to be written into the text of the
predecessor agreement, with twenty-four revisions identified.
Some revisions are short and straightforward: “Delete Letter
25 and Letter 30.” J.A. 729. Other revisions specify new
language for existing articles, increase certain reimbursement
rates and weekly wages, or set conditions for new Company
roles. The Memorandum addresses 401(k) retirement benefits
as follows: “The Company agrees to acknowledge the
provision of a 401(k) benefit to bargaining union [sic: unit]
employees in the drafting of the collective bargaining
agreement.” J.A. 729.
The Company and Union did not complete the revised
document incorporating their negotiated revisions into the
existing contract until almost a year later. The cover page of
that contract document as distributed late in 2017 is nearly
identical to the cover page of the 2016 Memorandum of
Agreement. The only difference is that actual signatures
appeared on the cover page of the Memorandum, whereas the
signatories’ names were typed on the cover of the document as
posted and circulated. But the signatories are the same, and
both documents show September 16, 2016, as the signing date.

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Indeed, the Company signatory whose name is typed in is Keith
Halpern—who represented DexYP at negotiations during 2016
and hand signed the Memorandum of Agreement—even
though he no longer worked for the Company when the revised
contract document was produced with his name typed on it in
2017.
Central to the current dispute, the revised contract
document as circulated includes specific language about the
401(k) benefit that is absent from the 2016 Memorandum of
Agreement. Whereas the Agreement states only that the
Company would “acknowledge the provision of a 401(k)
benefit,” the circulated contract document says: “The
Company 401K matching rate for all bargaining unit
employees will be no less than 100% for each employee dollar
contributed to individual accounts up to 5% maximum
contribution.” J.A. 371, 729. The question here is which of
those terms reflects the binding agreement of the parties.
To resolve which 401(k) term controls, the Board
considered the parties’ bargaining history for the 401(k) term
and made factual findings. In brief, the Board recounted the
following series of events.
In the negotiation for the 2016 Collective Bargaining
Agreement, the Union sought to secure a labor-contract term
protecting employees’ 401(k) benefits. Over the course of
negotiations, the Union twice unsuccessfully sought to secure
a specific level of employer match of employees’ 401(k)
contributions. In June 2016, the Union proposed “to change
the Company matching rate so that all bargaining unit
employees receive[d] a Company match of 100% for each
employee dollar contributed to individual accounts up to 6%
maximum contribution.” J.A. 776 (Resp. Exh. 6 – Company-
Held Bargaining Proposals and Bargaining Notes). YP

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Midwest Publishing rejected the offer. Later that month, the
Union proposed a 100 percent employer match up to 5 percent
maximum contribution. The Company also rejected that offer.
After the Union and YP Midwest Publishing failed to
reach agreement on the amount of a 401(k) match, they settled
on a compromise to prevent the employer from eliminating the
benefit: Teri Pluta, the lead Union negotiator, and Keith
Halpern, the lead Company negotiator, agreed to “have
language in the contract that guarantees the 401(k).” J.A. 161.
As Pluta later testified, the Union’s negotiating committee
members anticipated the change in Company ownership that in
fact took place in June 2017, and they “fear[ed] that . . . a new
owner may or may not honor collective bargaining agreements,
past practice, [or] provide the same type of benefits, so it
became more important to [the] committee to make sure that
they could get some guarantees there.” J.A. 159.
Steve Flagler, a Company attorney, testified that the
Company never agreed to a 5 percent 401(k) match during the
pre-ratification negotiations, but only agreed to “have a
reference in the contract to the fact that there was a 401(k) plan
offered to [the Union’s] members.” J.A. 114. Testifying as a
rebuttal witness, Pluta repeatedly acknowledged on cross
examination that the Company never agreed during
negotiations to a 5 percent 401(k) match, and that “language
that would guarantee the 401(k)” was “the very last item that
sealed the deal . . . .” J.A. 187.
At the close of negotiations in September 2016, employer
and Union representatives drafted and signed the 2016
Memorandum of Agreement. Shortly after the negotiators
signed the Memorandum of Agreement, the bargaining unit
members and the Company’s Board of Directors both ratified
the new Collective Bargaining Agreement as memorialized in

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the Memorandum of Agreement. That Collective Bargaining
Agreement became effective for a three-year term.
Almost a year later, after Dex Media Holdings acquired
the Company, the Company and Union completed the revised
document incorporating their negotiated revisions into the
existing contract. In April 2017, seven months after
negotiations concluded, Union representative Teri Pluta
emailed the Company’s labor counsel, Brian Herman, and
asked why the revised contract was not yet ready. Herman
emailed a document eleven days later, with redlines marking
the changes from the 2013 contract. No party representative
remarked on the 5 percent language at the time, but Teri Pluta
later testified that it was in “the first draft that came from YP.”
J.A. 164. In September 2017, Pluta emailed back to Steve
Flagler, another Company attorney, a clean version of the
document, explaining that she had accepted the redlined
revisions and fixed an error: a missing wage scale for a new
position the parties agreed to in the 2016 negotiations. In that
email, Pluta told Flagler that the document was ready to be
posted as the updated contract.
Flagler responded that he would post the contract to the
Company intranet and print copies for the local unions. Flagler
and Herman reviewed the document before posting it to the
intranet. As Flagler later acknowledged, he “missed” the
reference to a 5 percent match when he reviewed the post-
ratification revisions. J.A. 116.
There was no substantive discussion or approval action by
either side beyond the October 2016 ratification vote by the
bargaining unit members and approval by YP Midwest
Publishing’s Board of Directors. Pluta testified that, in the
interim between the April 2017 and the September 2017
emails, the Union and the Company had no discussions about

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401(k) benefits and exchanged no other versions of the revised
contract.
A month after Company representative Steve Flagler
posted the updated document, a local Union vice president
alerted a Union representative that the Company was planning
changes to the 401(k) benefits plan in 2018. After the Union
representative asked DexYP to send information on the new
plan, the Company sent a benefits summary showing that the
2018 benefits plan would maintain a maximum 4.8 percent
employer matching contribution but change to a more generous
matching formula. The 2016 Company benefits plan had
included an 80% match on employee contributions up to 6% of
employee compensation, which the 2018 plan replaced with a
graduated, front-loaded match formula, matching 100% of
employee contributions for the first 3% of compensation and
60% of contributions for the next 3%.
II. Decision on Review
In 2018, the Union brought an unfair labor practice charge
against DexYP over the Company’s 2018 retirement benefits
plan. The Union argued that DexYP violated the Collective
Bargaining Agreement by adopting a retirement benefits plan
that did not comply with the language in the revised document
guaranteeing a 100% match of employee contributions up to
5% of compensation. After investigating the charge, the
Board’s Regional Director brought a complaint alleging that
DexYP unilaterally changed the 401(k)-contribution formula,
along with other allegations that the parties later settled.
Defending against the complaint at a hearing before the
Board administrative law judge (ALJ), DexYP argued that the
5 percent match language in the Collective Bargaining
Agreement resulted from a drafting error. The Company
introduced—without objection from the Board’s General

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Counsel or the Union—the 2016 Memorandum of Agreement
that the parties signed at the close of negotiations.
DexYP also sought to introduce other evidence: testimony
about the 2016 negotiations and bargaining notes from those
sessions. The General Counsel and the Union objected,
arguing that the parol evidence rule barred evidence about the
negotiations. The ALJ admitted the testimony about the 2016
negotiations and associated bargaining notes under the mistake
exception to the parol evidence rule. Under that exception, the
Board allows oral testimony to show that a written agreement
contains an obvious mistake. Apache Powder Co., 223
N.L.R.B. 191, 191 (1976). The ALJ noted when she decided
to hear parol evidence that the parties would have an
opportunity to address, in their post-hearing briefs, whether a
mistake occurred and whether the ALJ should ultimately
consider the parol evidence in the decision. The parol evidence
included the above-described testimony of Company
negotiator Steve Flagler and Union negotiator Teri Pluta about
the 2016 negotiations and the process of revising the contract
document for posting in 2017.
In a written decision after the hearing, the ALJ
recommended that the Board dismiss the complaint. YP
Midwest Publ’g, LLC, 371 N.L.R.B. No. 23, at 9 (Aug. 26,
2021). Analyzing witness credibility, the ALJ “did not find
much of [Union negotiator Teri] Pluta’s testimony credible”
because “[s]he sparred with Respondent’s counsel on cross-
examination, gave contradictory testimony, and testified in an
equivocal manner.” Id. at 5. The ALJ generally credited the
other witnesses who testified.
The ALJ found that “[t]he only agreement reached by the
parties at the bargaining table regarding the 401(k) benefit was
that [the Company] would acknowledge its provision to its

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union-represented employees in the collective bargaining
agreement.” Id. at 7. The parties reached “[n]o agreement” on
the matching amount for employer 401(k) contributions. Id.
Under those circumstances, the ALJ concluded, “the negotiated
agreement that the [Memorandum of Agreement] would
contain a memorialization of the existence of [the Company’s]
401(k) program controls.” Id.
The ALJ concluded that considering parol evidence from
the parties’ negotiations was appropriate because, under the
Board’s holding in Apache Powder, 223 N.L.R.B. at 191, “the
parol evidence rule does not operate to exclude testimony
offered to establish that no agreement was reached in the first
place.” YP Midwest Publ’g, 371 N.L.R.B. at 6. The ALJ found
that neither the Company nor its predecessors had ever
“matched represented employees’ [401(k)] contributions at 5
percent,” and, based on the evidence regarding the 2016
negotiations, “[t]he record evidence conclusively established
that a 5 percent match was never agreed to in bargaining.” Id.
at 6-7. The ALJ found that, during negotiations, “the parties
only agreed to memorialize the existence of [DexYP’s] 401(k)
program,” that “[n]o specified amount of employer match was
ever established,” and that the Company mistakenly included
the 5 percent match in the revised contract. Id. at 6-8. The ALJ
found that the parties engaged in no further negotiations, nor
did they discuss any change in positions, between the close of
negotiations in fall 2016 and the revision of the contract
document in summer 2017. See id. at 4. As to whether the
Company’s inclusion of a 5 percent 401(k) match in its redline
markup of the predecessor agreement was an error that should
have been obvious to the Union, the ALJ did not credit Pluta’s
testimony that she believed the matching amount was
“language as promised” from the Company, J.A. 199, and not
“inconsistent” with the 401(k) match the members were

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receiving or with the negotiators’ agreement to acknowledge
the 401(k) plan, J.A. 200.
On administrative appeal, the Board affirmed the ALJ’s
findings and conclusions. Id. at 1. Like the ALJ, the Board
accepted the 2016 Memorandum of Agreement as
memorializing the agreement the parties reached in their
negotiations. Id. at 1 n.2. Analyzing the Memorandum of
Agreement, the Board concluded that the parties agreed the
Company would “acknowledge the provision of a 401(k)
benefit” in the revised contract but did not agree to any specific
matching percentage. Id. (emphasis in original). The Board
sustained the ALJ’s admission of parol evidence of the 2016
negotiations under Apache Powder. Id. (citing Apache
Powder, 223 N.L.R.B. at 191). After considering that
evidence, the Board held that DexYP’s “drafting error should
have been clearly obvious to the Union” given YP Midwest
Publishing’s “clear rejection of the Union’s proposal for a 5
percent match” and the lack of any “basis for the Union to
assume that [the Company] had changed its position on that
proposal.” Id.
The Union petitioned for review. DexYP, now operating
under the name Thryv, Inc., intervened in support of the Board.
DISCUSSION
The Union argues that the Board erred by crediting the
401(k) retirement-benefit term in the parties’ 2016
Memorandum of Agreement, admitting parol evidence, and
finding that the revised Collective Bargaining Agreement
circulated and posted as the final 2016-2019 contract reflected
a drafting error. We hold that the Board acted in accordance
with the law, including its own precedent, and that substantial
evidence supports its findings.

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I. Standard of Review
We review the Board’s administrative adjudications with
“a very high degree of deference.” Ozburn-Hessey Logistics,
LLC v. NLRB, 833 F.3d 210, 217 (D.C. Cir. 2016) (quoting
Bally’s Park Place, Inc. v. NLRB, 646 F.3d 929, 935 (D.C. Cir.
2011)). Within that limited scope of review, “we must uphold
the judgment of the Board unless its findings are unsupported
by substantial evidence, or it acted arbitrarily or otherwise
erred in applying established law to the facts of the case.”
Novato Healthcare Ctr. v. NLRB, 916 F.3d 1095, 1100 (D.C.
Cir. 2019). Where a party challenges the Board’s application
of its own precedent, we review whether the Board’s decision
was “arbitrary, capricious, an abuse of discretion, or otherwise
not in accordance with law.” 5 U.S.C. § 706(2)(A); Leggett &
Platt, Inc. v. NLRB, 988 F.3d 487, 494 (D.C. Cir. 2021). So
long as the Board offers a well-reasoned interpretation of its
precedent, we defer to that interpretation. Ceridian Corp. v.
NLRB, 435 F.3d 352, 355 (D.C. Cir. 2006).
We review factual findings supporting the Board’s
contract interpretation under the substantial evidence standard,
“including evidence of intent from bargaining history, and
other factual findings on matters bearing on the intent of the
parties.” Pac. Mar. Ass’n v. NLRB, 967 F.3d 878, 884-85 (D.C.
Cir. 2020) (quoting StaffCo of Brooklyn, LLC v. NLRB, 888
F.3d 1297, 1302 (D.C. Cir. 2018)); 29 U.S.C. § 160(e). We
owe no special deference to the Board’s interpretation of
contract language, but review it de novo, applying “ordinary
principles of contract law.” Pac. Mar. Ass’n, 967 F.3d at 885
(quoting M & G Polymers USA, LLC v. Tackett, 574 U.S. 427,
435 (2015)).

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II. The Board Correctly Identified the Binding
Agreement and 401(k) Term
We first consider the Union’s argument that the Board
erred by treating the 2016 Memorandum of Agreement as
authoritative rather than the document produced the following
year and circulated as the final revised contract. The Union
argues that the Board’s precedent required it to credit the
401(k) term in the revised contract document over the term
reflected in the Memorandum of Agreement. We review that
challenge in two steps. We first consider whether the Board
reasonably applied its precedent regarding when a collective
bargaining agreement is formed. We then address whether
substantial evidence supports the Board’s finding that the 2016
Memorandum of Agreement reflects the parties’ agreement on
the 401(k) term.
We hold that the Board followed its own precedent by
looking to the Memorandum of Agreement for the substance of
the parties’ agreed 401(k) term. The 401(k) terms in the two
relevant documents conflicted. The parties agreed in the 2016
Memorandum of Agreement only to “acknowledge” the
“provision” of a 401(k) benefit, whereas the document posted
in 2017 promised a 401(k) benefit whereby the employer
would match employees’ own contributions of up to 5 percent
of their salary. To decide which term controlled, the Board
followed its established approach for deciding when the parties
reached a meeting of the minds and which terms controlled at
that time.
Under Board precedent, “[i]t is well-established that a
collective bargaining agreement is formed after a meeting of
the minds on substantive issues and material terms.” Cnty.
Concrete Corp., 366 N.L.R.B. No. 64, at 9 (2018). The
meeting of the minds “is measured not by parties’ subjective

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inclinations, but by their intent as objectively manifested in
what they said to each other.” Id. (quoting Crittenton Hosp.,
343 N.L.R.B. 717, 718 (2004)).
To decide when the parties agreed on material terms, the
Board looks to “mutual expressions of satisfaction about the
successful negotiation of a contract [as] ‘hallmark indication[s]
that a binding agreement has been reached at the end of
negotiations.’” ABM Parking Servs., 360 N.L.R.B. 1191, 1204
(2014) (quoting Chauffeurs Loc. Union No. 771, 357 N.L.R.B.
2203, 2207 (2011)). For example, the Board has held that an
employer and a union reached a meeting of the minds at a
negotiating session where the parties “concluded that session
with handshakes and mutual expressions of satisfaction on their
successful negotiation of a contract.” Windward Teachers
Ass’n, 346 N.L.R.B. 1148, 1150-51 (2006); see also
Chauffeurs Loc. Union No. 771, 357 N.L.R.B. at 2207. The
Board likewise discerned a meeting of the minds where an
employer’s “remarks . . . were the email equivalent of shaking
hands on the deal at the end of a face to face meeting.” ABM
Parking Servs., 360 N.L.R.B. at 1204. By the same token,
bargaining unit employees’ “unqualified ratification” of an
expired predecessor collective bargaining agreement together
with a document reflecting “all of the agreed-on contract
changes” similarly sufficed to show that the parties reached a
binding agreement. Graphic Commc’ns Union, 318 N.L.R.B.
983, 992 (1995).
A collective bargaining agreement may be binding before
the parties reduce it to a final written form. To be sure, “once
an agreement is reached, each party is obligated to assist in
reducing the agreement to writing.” Ebon Servs., 298 N.L.R.B.
219, 223 (1990). But the Board has long followed the rule that
“offer and acceptance, not execution, make a labor contract.”
Sarauer v. Int’l Ass’n of Machinists & Aerospace Workers,

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Dist. No. 10, 966 F.3d 661, 677 (7th Cir. 2020). “Once an
agreement is reached by the parties, they are obligated to abide
by the terms of the agreement even though those terms have
not been reduced to writing.” Cnty. Concrete Corp., 366
N.L.R.B. at 1 n.1 (quoting Sunrise Nursing Home, Inc., 325
N.L.R.B. 380, 389 (1998)). Indeed, “[t]he question of contract
formation is based on the parties’ expressed intentions
regarding the terms of a collective-bargaining agreement,”
which may establish a contract was formed even in advance of
any document being signed. Sunrise Nursing Home, Inc., 325
N.L.R.B. at 389. Once the parties reach agreement, ensuing
back-and-forth about the contract may be “merely
communications aimed at converting their agreement into a
complete, written contract.” ABM Parking Servs., 360
N.L.R.B. at 1204.
The Board’s treatment of collective bargaining agreements
as binding before they are reduced to a final writing helps to
protect the bargaining process. For example, the Board has
held that a party that refuses to sign an agreement after
acquiescing to its terms during negotiations “impairs the
bargaining process and tends to frustrate the aim of the
[National Labor Relations Act] to secure industrial peace
through collective bargaining.” H. J. Heinz v. NLRB, 311 U.S.
514, 526 (1941). To avoid those problems, the Board treats the
refusal to sign a written contract after reaching agreement on
its terms through negotiation as an unfair labor practice under
Section 8(b)(3) of the National Labor Relations Act.
Windward Teachers, 346 N.L.R.B. at 1150.
Applying those principles to this case, the Board did not
need to look for handshakes or email acceptances. The record
contains direct evidence of the terms the parties reached during
negotiations: the signed September 2016 Memorandum of
Agreement. The Board’s decision to credit the 2016

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Memorandum of Agreement as reflecting the parties’ agreed
401(k) term accords with its established precedent referencing
the “meeting of the minds” to identify when the parties reached
a binding agreement and to treat as authoritative the terms they
agreed to at that time.
Substantial evidence supports the Board’s conclusion that
the Memorandum of Agreement represented the parties’
binding agreement on the 401(k) term. The Memorandum of
Agreement stated that the “Union and Employer collectively
have reached agreement and the predecessor agreement shall
only be revised as specifically set forth herein.” J.A. 709. The
employer and Union representatives signed the cover page and
initialed each page. The bargaining unit members and the
Company’s Board of Directors ratified the 2016 Memorandum
of Agreement as their negotiated updates to the predecessor
Collective Bargaining Agreement. By signing an agreement
stating that the prior contract would be revised only as
specifically agreed in the Memorandum of Agreement, and by
sending that package through the ratification process, the
parties showed that they regarded the Memorandum of
Agreement as the binding document memorializing their new
Collective Bargaining Agreement.
The leisurely way the parties went about revising the 2013
contract’s text to reflect the agreed-to changes reinforces the
importance of the 2016 Memorandum of Agreement. It was
not until April 2017, seven months after signing the
Memorandum of Agreement, that Union representative Teri
Pluta asked DexYP counsel Brian Herman why the Company
had not yet sent the Union a document incorporating the
negotiated changes into the preexisting contract. Herman sent
a redlined document eleven days later, and Pluta took nearly
five more months to return it to him, writing that she had
accepted the revisions and included a missing wage scale for a

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new position. The parties apparently never even pointed out or
acknowledged during the revision process the 5 percent
matching term that appeared in the revised contract document,
and they expressed confusion before the ALJ about how it got
there. The bargaining unit members and the Company’s Board
of Directors had ratified the Memorandum of Agreement in
2016; neither party undertook any ratification process for the
revised contract document in 2017.
The cover page of the revised contract document refers to
September 16, 2016, as the date of the agreement. The cover
pages of both the 2016 Memorandum of Agreement and the
contract package as revised, posted, and circulated in 2017
reflect that same September 2016 date—when Company and
Union negotiators signed the 2016 Memorandum of
Agreement, not when Herman and Pluta finished incorporating
the changes into the text of the predecessor agreement or when
the Company posted it on its intranet. The signatories are the
same—with signatures handwritten on the September 2016
Memorandum of Agreement and the same names typed on the
revised version circulated to employees in 2017—even though
the employer’s signatory, Keith Halpern, no longer worked for
the Company when the revision was done. Halpern’s
replacement, Brian Herman, supervised the revision process,
but Halpern’s is the only name that appears on the final version.
The timing of the parties’ ratification of the contract terms,
together with the casual pace at which the parties later
incorporated the negotiated revisions into the predecessor
agreement, supports the Board’s conclusion that it was the
Memorandum of Agreement that was binding. The use of the
same employer signatory even after his departure from the
Company reinforces that the parties’ agreement was finalized
in September 2016, not 2017. Substantial evidence supports
the Board’s finding that the 401(k) term in the ratified 2016

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Memorandum of Agreement, not the post-ratification revision,
reflects the parties’ binding agreement.
III. The Board Permissibly Considered Parol
Evidence
Next, we review the Board’s application of the parol
evidence rule. The Union argues that the Board incorrectly
relied on Apache Powder, 223 N.L.R.B. 191, to admit
testimony and bargaining notes relating to the 2016
negotiations to discern the Company’s mistake. In the Union’s
view, the Board should have instead followed its precedent in
Windward Teachers Association, 346 N.L.R.B. 1148 (2006),
and Ebon Services, 298 N.L.R.B. 219 (1990), two cases in
which the Board rejected a mistake defense and enforced a
collective bargaining agreement as written. That precedent,
says the Union, requires enforcement of the term inserted in the
2017 contract revision rather than the term reflected in the 2016
Memorandum of Agreement. We must determine whether, in
looking to parol evidence to resolve that claim, the Board
arbitrarily and capriciously departed from its precedent. ABM
Onsite Services-W., Inc. v. NLRB, 849 F.3d 1137, 1146 (D.C.
Cir. 2017).
The Board recognized the mistake exception to the rule
against parol evidence in Apache Powder when it held that “the
parol-evidence rule does not operate to exclude testimony
offered to establish that in fact no agreement was reached in the
first place.” 223 N.L.R.B. at 191. The employer in Apache
Powder had refused to sign a collective bargaining agreement
because, it claimed, the agreement the parties initialed and
ratified contained a mistake. Id. at 193-94. It sought to offer
parol evidence to show that, during negotiations, it
inadvertently proposed a start date for higher monthly pension
benefits a year earlier than the parties intended. Id. at 194. The

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21
ALJ admitted the parol evidence, recognizing that evidence
outside an agreement “may be introduced for the purpose of
ascertaining the correct interpretation of an agreement, as well
as to establish the nonexistence of an agreement.” Id. (internal
citations omitted). After considering the parol evidence, the
ALJ found that the start date was indeed a drafting error. Id.
The Board affirmed. Id. at 191. The Board cautioned that
“rescission for unilateral mistake is, for obvious reasons, a
carefully guarded remedy,” but held the standard met because
the start-date mistake was “so palpably at odds with the pension
provisions of the existing contract as to put the [union] on
notice of an obvious mistake by the [employer].” Id.
Apache Powder established two rules relevant here: First,
parol evidence is admissible to establish whether an agreement
was reached; second, a unilateral mistake occurs “where the
mistake is so obvious as to put the other party on notice of an
error.” Id.
The Board has consistently relied on the Apache Powder
formulation of the mistake exception to the parol evidence rule.
In some decisions, the Board discusses parol evidence before
concluding that no mistake occurred and enforcing an
agreement as written. See, e.g., Monterey/Santa Cruz Bldg.
Trades Council (Nat’l Refractories), 299 N.L.R.B. 251, 257
(1990). In others, the ALJ admits parol evidence at the hearing
but, on consideration, finds no need to refer to it in the written
decision. See, e.g., Sheehy Enterprizes, Inc., 353 N.L.R.B. 803,
805 n.1 (ALJ decision), 806 (2009). Other Board decisions,
like Apache Powder and the decision under review, consider
parol evidence and, based on the bargaining history it discloses,
conclude that the written agreement contains a mistake. See,
e.g., Waldon, Inc., 282 N.L.R.B. 583, 584-86 (1986); Cook
Cnty. Sch. Bus, Inc., 333 N.L.R.B. 647, 653 (2001), enforced,

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22
283 F.3d 888, 896 (7th Cir. 2002); Globe-Union, Inc., 245
N.L.R.B. 145, 147 (1979).
The mistake exception finds support not only in Board
precedent, but in accepted principles of generally applicable
contract law. See M & G Polymers, 574 U.S. at 430, 433
(2015). Contract doctrine recognizes that “oral testimony is
admissible to prove fraud or misrepresentation, mistake, or
illegality.” 6 Corbin on Contracts § 25.20 (2022). “Such
invalidating causes need not and commonly do not appear on
the face of the writing.” Restatement (Second) of Contracts
§ 214 (2022). And, “[s]ince the application of the parol
evidence rule depends on the existence of a valid integrated
contract, the rule does not preclude evidence which contradicts
the very existence or validity of an alleged contractual
obligation.” 11 Williston on Contracts § 33:14 (4th ed. 2022).
Our dissenting colleague argues that the 2016 signed and
ratified Memorandum of Agreement is itself parol evidence.
Diss. Op. at 2. But as explained, that Memorandum of
Agreement is itself the agreement that binds the parties.
Necessarily, then, it is not parol evidence. And indeed, the
Union and the Board’s General Counsel never objected to
consideration of that document as parol evidence. At the
hearing before the ALJ, neither the Union nor General Counsel
objected when the Company introduced the Memorandum of
Agreement. They raised the parol evidence objection only to
oral testimony about the negotiations preceding that signed
contract.
The Union argues that by admitting parol evidence in this
case the Board departed from its decisions in Windward
Teachers Association, 346 N.L.R.B. 1148, and Ebon Services,
298 N.L.R.B. 219. Because the Board in those two cases
enforced written contract terms, the Union reasons, the Board

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23
should enforce the revised contract’s terms here. But the Board
in both of those cases considered oral testimony about the
parties’ bargaining history before concluding that the written
terms accurately reflected the parties’ agreement at the close of
negotiations. Windward Teachers, 346 N.L.R.B. at 1148-50;
Ebon Servs., 298 N.L.R.B. at 220-22. The Union’s objection
here is accordingly reduced to a challenge to the Board’s
factual finding that the revised contract contained a drafting
error, not the ALJ’s admission of parol evidence to consider
whether a mistake occurred.
IV. Substantial Evidence Supports the Board’s
Mistake Finding
We next consider whether substantial evidence supports
the Board’s finding that the specific 401(k) language in the
revised document was a mistake. The Board found that “it
should have been obvious to the Union that the inclusion of a
specific matching percentage of 5 percent did not reflect the
parties’ understanding and was a drafting error.” YP Midwest
Publ’g, LLC, 371 N.L.R.B. at 1 n.2. To so find, the Board
applied the standard for unilateral mistake from Apache
Powder: A finding of unilateral mistake is a “carefully guarded
remedy,” appropriate “where the mistake is so obvious as to
put the other party on notice of an error.” 223 N.L.R.B. at 191.
The Union challenges that determination, arguing that even if
the employer mistakenly added the 5 percent match language
to the draft, the mistake was not obvious enough to place the
Union on notice. Substantial evidence supports the Board’s
finding to the contrary.
De novo review of the dueling contract terms themselves
does not reveal whether the 401(k)-benefit term offering a 5
percent match resulted from a mistake. Where contract
language contains a drafting error, the mistake “commonly

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24
do[es] not appear on the face of the writing.” Restatement
(Second) of Contracts § 214. The mistake here is apparent only
in light of the Board’s findings about the bargaining history.
The deference we owe to the Board’s findings of fact extends
to its findings that describe bargaining history and provide
context showing when and how the parties reached agreement.
See Pac. Mar. Ass’n, 967 F.3d at 885.
The facts of the parties’ course of bargaining reveal that
they had reached a complete and binding agreement in
September 2016, when the parties signed the Memorandum of
Agreement stating they would “acknowledge” the 401(k)
benefit, and that the parties promptly ratified the agreement on
that basis. J.A. 729. Their binding agreement did not include
the language guaranteeing a 5 percent match, which was only
mistakenly inserted the following year during the process of
updating the predecessor contract for circulation. See supra at
18-20. Several of our sister circuits have looked to ratification
as the “last act necessary” to create an enforceable labor
contract. Sarauer, 966 F.3d at 676; Mack Trucks, Inc. v. United
Auto, Aerospace & Agr. Implement Workers of Am., 856 F.2d
579, 592 (3d Cir. 1988); NLRB v. Deauville Hotel, 751 F.2d
1562, 1569 n.10 (11th Cir. 1985); Sw. Airlines Co. v. Loc. 555,
Transp. Workers Union of Am., 912 F.3d 838, 846-47 (5th Cir.
2019). On that logic, the Seventh Circuit affirmed a Board
finding of mistake where a drafter introduced a post-ratification
typo into a contract. NLRB v. Cook Cnty. Sch. Bus, Inc., 283
F.3d 888, 895-96 (7th Cir. 2002). There, the Seventh Circuit
observed that bargaining unit members ratified an earlier
synopsis without the typo and had never voted to adopt the
later-appearing “actual agreement,” which a union
representative had finalized (with a typo) “merely for signature
by the head honchos.” Id. at 895.

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Enforcing the ratified agreement here—rather than the
revised contract document as circulated and posted—is
unassailable where the record contains no evidence of
“renegotiation of the agreement’s terms” after the date of
ratification. Sarauer, 966 F.3d at 676. Again, YP Midwest
Publishing negotiator Steve Flagler and Union negotiator Teri
Pluta both testified that the Union never persuaded the
Company during negotiations to agree to a 5 percent 401(k)
match. Yet the language that ultimately ended up in the
agreement—language nearly identical to the language that the
Company had rejected in June 2016—called for a 5 percent
match. Under those circumstances, substantial evidence
supports the Board’s conclusion that the 5 percent match was a
drafting error that should have been obvious to the union.
The Union argues that the Board erred by not following
Ebon Services, 298 N.L.R.B. at 219 n.2, 223 and Windward
Teachers, 346 N.L.R.B. at 1151, to hold that parties are bound
by language they reviewed and agreed to sign. The Board
should have held the 5 percent 401(k) match term binding, says
the Union, because it was consistent with the term of the 2016
Memorandum of Agreement, so not a mistake. The cases on
which the Union relies are consistent with the Board’s
approach to determining when a binding agreement was
reached in the first place. In Ebon Services and Windward
Teachers, parties successfully challenged their counterparties’
refusals to sign agreements with language they had agreed to at
the close of negotiations. Ebon Servs., 298 N.L.R.B. at 219
n.2; Windward Teachers, 346 N.L.R.B. at 1151. In both cases,
the Board considered oral testimony about the parties’
negotiations, then decided that the written terms accurately
reflected the parties’ agreement at the close of negotiations.
Ebon Servs., 298 N.L.R.B. at 224-25; Windward Teachers, 346
N.L.R.B. at 1149-50. Specifically, the employer in Ebon
Services, having read over the agreement and verbally agreed

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26
to sign, ultimately refused to sign even though “there was no
mutual mistake or misunderstanding about any of the terms” in
the agreement. 298 N.L.R.B. at 224-25. And in Windward
Teachers, the union claimed mistake and so refused to sign an
agreement even though the disputed language had been present
in the draft agreement during the final negotiating session when
the parties reached agreement. 346 N.L.R.B. at 1149. The
Board’s decision in this case reflects the same approach it has
used in prior cases to identify the terms the parties agreed to in
negotiations and enforce the written agreement memorializing
those terms.
The Board recognizes that resorting to parol evidence to
find a unilateral mistake in a written agreement is reserved for
“unusual instance[s].” Apache Powder, 223 N.L.R.B. at 191.
Rightly so. Consistent with that recognition, the Board in the
decades since Apache Powder has declined to recognize
unilateral mistake in the absence of a mistake so obvious as to
communicate to the opposing party that it was unlikely to have
been intended. For example, the Board has rejected a mistake
defense where a union negotiator “hurriedly glanced at” a side
letter before approving it, then later argued that he did not
intend to agree to the letter’s terms. Television Artists AFTRA
(Eleven-Fifty Corp.), 310 N.L.R.B. 1039, 1041, 1044 (1993).
The Board has also declined to find mistake where a negotiator
made incorrect assumptions before agreeing to a contract term.
Nat’l Refractories, 299 N.L.R.B. at 257. The reasoning in
those cases, as here, treats as binding the terms that the parties
agreed to and submitted for ratification at the conclusion of
their negotiations. Id.; Eleven-Fifty Corp, 310 N.L.R.B. at
1043. Here, the parol evidence of the parties’ bargaining
history allowed the Board to identify the Memorandum of
Agreement as the final product of the parties’ negotiations, and
to conclude that the 401(k) term in the 2017 revised version of

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the Collective Bargaining Agreement contained an
unenforceable unilateral mistake.
* * *
For the foregoing reasons, we deny the petition for review.
So ordered.

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SENTELLE , Senior Circuit Judge, dissenting: This case
presents a straightforward contract dispute between
Communications Workers of America (“the Union”) and
DexYP (“the Company”). The Union and the Company
negotiated. They reduced their negotiations to a written
agreement, the Collective Bargaining Agreement (“CBA”).
And both parties signed the agreement. That is the end of the
story. The National Labor Relations Board in the opinion
under review erred in accepting parol evidence to rewrite that
agreement. In this Court, the majority cites Williston and
Corbin for the proposition that a court may review parol
evidence in the cases of fraud, misrepresentation, or lack of a
valid integrated contract. Op. at 22. But there is an even more
fundamental rule of contracts: courts hold parties to their
bargains. See, e.g., NRM Corp. v. Hercules Inc., 758 F.2d 676,
681 (D.C. Cir. 1985) (“Where the language of a contract is
clear and unambiguous on its face, a court will assume that the
meaning ordinarily ascribed to those words reflects the
intentions of the parties.”).
First, the “mistake” in the 2017 CBA, supposedly
memorializing the parties’ 2016 Memorandum of Agreement
(“MOA”), is far from obvious. See Apache Powder Co., 223
N.L.R.B. 191, 191 (1976) (“[R]escission for unilateral mistake
is, for obvious reasons, a carefully guarded remedy reserved
for those instances where the mistake is so obvious as to put
the other party on notice of an error.”). First, the Company’s
attorney himself wrote the disputed 5% 401(k) contribution
term into the CBA. See Resp. Br. at 7–8. Then, he highlighted
the change by redlining the term before sending it to the
Union’s attorney. See id. This is perhaps an even worse
scenario for violation of the parol evidence rule than not
reading—and agreeing to—a term in a contract, a scenario in
which we still hold parties to their bargains. See Paterson v.
Reeves, 304 F.2d 950, 951 (D.C. Cir. 1962) (“One who signs a
contract which he had an opportunity to read and understand is
bound by its provisions.”). The Company wrote the term into

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2
the final contract and highlighted it for the Union to review. It
strains credulity to then penalize the Union for not recognizing
an “obvious” mistake in the term amount.
Second, the parties engaged in a full exchange. Neither
side suffered from a bargaining disadvantage or mismatched
negotiating skills. See BHM Healthcare Sols., Inc. v. URAC,
Inc., 320 F. Supp. 3d 1, 10 (D.D.C. 2018). The attorneys for
both sides exchanged the final agreement back and forth. The
parties have a right to rely on the document to which they both
agreed.
Third, courts take the parol evidence rule very
seriously, especially in cases of unilateral mistake, a point the
majority acknowledges. Op. at 21. But the majority here
tautologically uses parol evidence to prove it needs parol
evidence. The 2016 MOA is parol evidence. Relying on it to
conclude what the final, executed 2017 CBA means is to
therefore violate the parol evidence rule. If the 2016 MOA
represented the final, negotiated settlement between the parties,
as the majority contends, there would have been no need for
the Union and the Company to execute the 2017 CBA. The
majority claims the MOA is inconsistent with the as-executed
CBA including the 5% term, indicating a lack of a meeting of
the minds, but the MOA only included placeholder language
that the parties would later insert the term. See J.A. 729 (“The
Company agrees to acknowledge the provision of a 401(k)
benefit to bargaining union [sic: unit] employees in the drafting
of the collective bargaining agreement.”). Therefore, the 2016
MOA and the 2017 CBA are just as easily consistent with one
another.

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3
At base, the CBA is the final agreement. We must
adhere to the four corners of that document, in which both
parties agreed to a 5% 401(k) matching contribution term.
I respectfully dissent.

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