UNITED STATES

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☐	Soliciting material Pursuant to §240.14a-12

Automatic Data Processing, Inc.

(Name of Registrant as Specified In Its Charter)

William A. Ackman

Veronica M. Hagen

V. Paul Unruh

Pershing Square Capital Management, L.P.

PS Management GP, LLC

Pershing Square, L.P.

Pershing Square II, L.P.

Pershing Square International, Ltd.

Pershing Square Holdings, Ltd.

Pershing Square VI Master, L.P.

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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Pershing Square Capital Management, L.P. and certain affiliates (“Pershing Square”) posted the following material to their Facebook page relating to Automatic Data Processing, Inc. (the “Company”):

ADP Ascending Published by Global strategy Group [?] · 1 min
In recommending tnat ADP shareholders vote for ALL THREE of Pershing
Square’s nominees for ADP’s board of directors, leading independent proxy
advisory firm Glass Lewis highlighted ADP’s ineffective investment in
technological innovation and best in class products. Read more from Glass
Lewis’s report below:
“[W]hile ADP claims that its investmens and initiatives are yielding
productivity gains, any such gains appear to have been nominal and muted
relative to gains achieved by competitors. This outcome, among others,
including the Company’s inability to date to bring to market a competitive
product offering in the enterprise segment, support [Pershing Square’s) view
that while ADP isn’t underspending in technology and innovation ADP is
spending inefficiently and ineffectively.”

ADP Ascending Published by Global Strategy Group [?] · Jus! Now
“We believe [Pershing Square’s] nominees would each and collectively bring
a fresh independent perspective, new i:deas, recent and practical experience
achieving operational efficiencies, implementing a business transformation
plan and realizing cost savings, as well as financial expertise and an owner’s
mentality to the ADP board.· -Glass Lewis
Vote Online Vote By Phone Vote By Mail
Vote GOLD
to Help ADP
Achieve Its
Full Potential

Pershing Square posted the following material to their Twitter page relating to the Company:

ADP Ascending @ADPascendmg
Independent proxy advisory firm Glass Lewis
recommends $ADP shareholders #VoteGOLD
for our transformation plan.
Proxy Advisory Firm Glass Lewis Recommends AOP Share ...
Pershing Square Capital Management, L. P. (·Pershing Square·),
announced today that Glass, Lewis & Co., LLC (.Glass Lewis&rdq
businesswire.com
6:44 PM- 25 Oct 2017

ADP Ascending @ADPascending
Glass Lewis’s independent analysis of $ADP
“supports [the view] that ADP has not
delivered returns.” #VoteGOLD [1 / 2] 6:38 AM - 26 0ct 2017

ADP Ascending @ADPascending
Ind. analysis further “supports [the overall
thesis] that $ADP is not performing to its full
potential.” #VoteGOLD [2/2] 6:38 AM - 26 Oct 2017

ADP Ascending @ADPascending
Independent advisor @Giasslewis
recommends that $ADP Investors
#VoteGOLD. Get the story from Reuters –
Glass Lewis recommends AOP investors vote for Ackman·s ...
Bayliss
reuters.com
8:30 AM - 26 Oct 2017

ADP Ascending @ADPascending
.@GiassLewis backs ALL of the #VoteGOLD
nominees for ADP’s board. Read more in
@The Street:
Ackman Gets Boost In ADP Battle
lnftuential shareholder advisory firm supports all of the activist investor’s director
candidates in a proxy war set to conclude on Nov. 7.
thestreet.com.
11:00 AM- 26 Oct 2017