Document ID: ./input/supremecourt_opinions/opinions/17pdf/16-1454_5h26.pdf
Page Number: 17.0

Cite as:  585 U. S. ____ (2018) 

13 

Opinion of the Court 

behaves  much  like  a  one-sided  market  and  should  be 
analyzed  as  such.    See  Filistrucchi  321;  Times-Picayune 
Publishing Co. v. United States, 345 U. S. 594, 610 (1953). 
But two-sided transaction platforms, like the credit-card
market, are different.  These platforms facilitate a single, 
simultaneous transaction between participants.  For credit 
cards,  the  network  can  sell  its  services  only  if  a  mer- 
chant  and  cardholder  both  simultaneously  choose  to  use 
the  network.    Thus,  whenever  a  credit-card  network  sells 
one  transaction’s  worth  of  card-acceptance  services  to  a 
merchant it also must sell one transaction’s worth of card-
payment  services  to  a  cardholder.    It  cannot  sell  transac-
tion services to either cardholders or merchants individu-
ally.  See Klein 583 (“Because cardholders and merchants
jointly  consume  a  single  product,  payment  card  transac-
tions,  their  consumption  of  payment  card  transactions
must  be  directly  proportional”).    To  optimize  sales,  the
network must find the balance of pricing that encourages
the greatest number of matches between cardholders and
merchants. 

Because  they  cannot  make  a  sale  unless  both  sides  of 
the  platform  simultaneously  agree  to  use  their  services,
two-sided  transaction  platforms  exhibit  more  pronounced 
indirect  network  effects  and  interconnected  pricing  and
demand.  Transaction  platforms  are  thus  better  under-
stood  as  “suppl[ying]  only  one  product”—transactions.
Klein  580.  In  the  credit-card  market,  these  transactions 
“are  jointly  consumed  by  a  cardholder,  who  uses  the  pay-
ment  card  to  make  a  transaction,  and  a  merchant,  who 
accepts the payment card as a method of payment.”  Ibid. 
Tellingly,  credit  cards  determine  their  market  share  by 
measuring the volume of transactions they have sold.8 

—————— 

8 Contrary  to  the  dissent’s  assertion,  post,  at  11–12,  merchant  ser-
vices  and  cardholder  services  are  not  complements.  See  Filistrucchi 
297  (“[A]  two-sided  market  [is]  different  from  markets  for  complemen-