Document ID: ./input/supremecourt_opinions/opinions/11pdf/10-1150.pdf
Page Number: 7.0

Cite as:  566 U. S. ____ (2012) 

3 

Opinion of the Court 

and useful end”). 

Still, as the Court has also made clear, to transform an 
unpatentable law of nature into  a patent-eligible  applica-
tion of such a law, one must do more than simply state the 
law of nature while adding the words “apply it.”  See, e.g., 
Benson, supra, at 71–72. 

The case before us lies at the intersection of these basic 
principles.    It  concerns  patent  claims  covering  processes
that  help  doctors  who  use  thiopurine  drugs  to  treat  pa­
tients  with  autoimmune  diseases  determine  whether  a 
given dosage level is too low or too high.  The claims pur­
port  to  apply  natural  laws  describing  the  relationships 
between  the  concentration  in  the  blood  of  certain  thiopu­
rine  metabolites  and  the  likelihood  that  the  drug  dosage 
will be ineffective or induce harmful side-effects.  We must 
determine  whether  the  claimed  processes  have  trans­
formed  these  unpatentable  natural  laws  into  patent­
eligible applications of those laws.  We conclude that they
have not done so and that therefore the processes are not 
patentable.

Our conclusion rests upon an examination of the partic­
ular  claims  before  us  in  light  of  the  Court’s  precedents. 
Those  cases  warn  us  against  interpreting  patent  statutes
in ways that make patent eligibility “depend simply on the 
draftsman’s  art”  without  reference  to  the  “principles  un­
derlying  the  prohibition  against  patents  for  [natural
laws].”  Flook,  supra,  at  593.    They  warn  us  against  up­
holding  patents  that  claim  processes  that  too  broadly 
preempt  the  use  of  a  natural  law.    Morse,  supra,  at  112– 
120;  Benson,  supra,  at  71–72.  And  they  insist  that  a 
process  that  focuses  upon  the  use  of  a  natural  law  also
contain  other  elements  or  a  combination  of  elements, 
sometimes referred to as an “inventive concept,” sufficient
to  ensure  that  the  patent  in  practice  amounts  to  signifi­
cantly  more  than  a  patent  upon  the  natural  law  itself. 
Flook, supra, at 594; see also Bilski, supra, at ___ (slip op.,