Document ID: ./input/supremecourt_opinions/opinions/17pdf/16-1454_5h26.pdf
Page Number: 35

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

11 

BREYER, J., dissenting 

See, e.g., United States v. E. I. du Pont de Nemours & Co., 
351 U. S. 377, 395–396 (1956) (explaining that cellophane 
market  includes  other,  substitutable  flexible  wrapping 
materials  as  well).  The  reason  that  substitutes  are  in­
cluded in the relevant market is that they restrain a firm’s
ability  to  profitably  raise  prices,  because  customers  will 
switch to the substitutes rather than pay the higher prices.
See 2B Areeda & Hovenkamp ¶561, at 378. 

But  while  the  market  includes  substitutes,  it  does  not 

include  what  economists  call  complements:  goods  or  ser­
vices  that  are  used  together  with  the  restrained  product, 
but  that  cannot  be  substituted  for  that  product.    See  id., 
¶565a,  at  429;  Eastman  Kodak  Co.  v.  Image  Technical 
Services,  Inc.,  504  U. S.  451,  463  (1992).    An  example  of 
complements  is  gasoline  and  tires.    A  driver  needs  both 
gasoline and tires to drive, but they are not substitutes for
each other, and so the sale price of tires does not check the
ability  of  a  gasoline  firm  (say  a  gasoline  monopolist)  to
raise  the  price  of  gasoline  above  competitive  levels.  As  a 
treatise  on  the  subject  states:  “Grouping  complementary 
goods  into  the  same  market”  is  “economic  nonsense,”  and 
would  “undermin[e]  the  rationale  for  the  policy  against 
monopolization or collusion in the first place.”  2B Areeda 
& Hovenkamp ¶565a, at 431. 

Here,  the  relationship  between  merchant-related  card 
services  and  shopper-related  card  services  is  primarily
that  of  complements,  not  substitutes.  Like  gasoline  and
tires,  both  must  be  purchased  for  either  to  have  value.
Merchants  upset  about  a  price  increase  for  merchant-
related services cannot avoid that price increase by becom­
ing  cardholders,  in  the  way  that,  say,  a  buyer  of  newspa­
per  advertising  can  switch  to  television  advertising  or
direct mail in response to a newspaper’s advertising price 
increase.  The  two  categories  of  services  serve  fundamen­
tally  different  purposes.  And  so,  also  like  gasoline  and
tires,  it  is  difficult  to  see  any  way  in  which  the  price  of