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would be to allow the patentee to pre-empt substantially all uses of that fundamental 
principle.  If so, the claim is not drawn to patent-eligible subject matter. 
 In 
Diehr, the Court held that the claims at issue did not pre-empt all uses of the 
Arrhenius equation but rather claimed only "a process for curing rubber . . . which 
incorporates in it a more efficient solution of the equation."  450 U.S. at 188.  The 
process as claimed included several specific steps to control the curing of rubber more 
precisely:  "These include installing rubber in a press, closing the mold, constantly 
determining the temperature of the mold, constantly recalculating the appropriate cure 
time through the use of the formula and a digital computer, and automatically opening 
the press at the proper time."  Id. at 187.  Thus, one would still be able to use the 
Arrhenius equation in any process not involving curing rubber, and more importantly, 
even in any process to cure rubber that did not include performing "all of the other steps 
in their claimed process."  See id.; see also Tilghman v. Proctor, 102 U.S. 707, 729 
(1880) (holding patentable a process of breaking down fat molecules into fatty acids and 
glycerine in water specifically requiring both high heat and high pressure since other 
processes, known or as yet unknown, using the reaction of water and fat molecules 
were not claimed). 
In contrast to Diehr, the earlier Benson case presented the Court with claims 
drawn to a process of converting data in binary-coded decimal ("BCD") format to pure 
binary format via an algorithm programmed onto a digital computer.  Benson, 409 U.S. 
at 65.  The Court held the claims to be drawn to unpatentable subject matter: 
It is conceded that one may not patent an idea.  But in practical effect that 
would be the result if the formula for converting BCD numerals to pure 
binary numerals were patented in this case.  The mathematical formula 
involved here has no substantial practical application except in connection 
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