Document ID: ./input/supremecourt_opinions/opinions/09pdf/08-964.pdf
Page Number: 7.0

Cite as:  561 U. S. ____ (2010) 

3 

Opinion of the Court 

historical weather pattern.”  Id., at 21. 

The  patent  examiner  rejected  petitioners’  application,
explaining that it “ ‘is not implemented on a specific appa-
ratus  and  merely  manipulates  [an]  abstract  idea  and 
solves a purely mathematical problem without any limita-
tion  to  a  practical  application,  therefore,  the  invention  is 
not  directed  to  the  technological  arts.’ ”    App.  to  Pet.  for 
Cert.  148a.  The  Board  of  Patent  Appeals  and  Interfer-
ences  affirmed,  concluding  that  the  application  involved
only  mental  steps  that  do  not  transform  physical  matter
and was directed to an abstract idea.  Id., at 181a–186a. 

The  United  States  Court  of  Appeals  for  the  Federal 
Circuit  heard  the  case  en  banc  and  affirmed.    The  case 
produced  five  different  opinions.    Students  of  patent  law
would be well advised to study these scholarly opinions. 

Chief Judge Michel wrote the opinion of the court.  The 
court  rejected  its  prior  test  for  determining  whether  a 
claimed  invention  was  a  patentable  “process”  under 
§101—whether it produces a “ ‘useful, concrete, and tangi-
ble  result’ ”—as  articulated  in  State  Street  Bank  &  Trust 
Co.  v.  Signature  Financial  Group,  Inc.,  149  F. 3d  1368, 
1373  (1998),  and  AT&T  Corp.  v.  Excel  Communications, 
Inc.,  172  F. 3d  1352,  1357  (1999).    See  In re  Bilski,  545 
F. 3d  943,  959–960,  and  n. 19  (CA  Fed.  2008)  (en  banc).
The  court  held  that  “[a]  claimed  process  is  surely  patent-
eligible under §101 if: (1) it is tied to a particular machine 
or apparatus, or (2) it transforms a particular article into a 
different state or thing.”  Id., at 954.  The court concluded 
this  “machine-or-transformation  test”  is  “the  sole  test 
governing  §101  analyses,”  id.,  at  955,  and  thus  the  “test 
for determining patent eligibility of a process under §101,” 
id., at 956.  Applying the machine-or-transformation test, 
the court held that petitioners’ application was not patent 
eligible.  Id.,  at  963–966.  Judge  Dyk  wrote  a  separate
concurring  opinion,  providing  historical  support  for  the