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Corp. dissent is its failure to recognize the difference between a patent ineligible 
relationship—i.e., that between high homocysteine levels and folate and cobalamin 
deficiencies—and a patent eligible process for applying that relationship to achieve a 
useful, tangible, and concrete result—i.e., diagnosis of potentially fatal conditions in 
patients.  Nothing abstract here.  Moreover, testing blood for a dangerous condition is 
not a natural phenomenon, but a human invention. 
The distinction is simple but critical:  A patient may suffer from the unpatentable 
phenomenon of nature, namely high homocysteine levels and low folate.  But the 
invention does not attempt to claim that natural phenomenon.  Instead the patent claims 
a process for assaying a patient’s blood and then analyzing the results with a new 
process that detects the life-threatening condition.  Moreover, the sick patient does not 
practice the patented invention.  Instead the patent covers a process for testing blood 
that produces a useful, concrete, and tangible result:  incontrovertible diagnostic 
evidence to save lives.  The patent does not claim the patent ineligible relationship 
between folate and homocysteine, nor does it foreclose future inventors from using that 
relationship to devise better or different processes.  Contrary to the language of the 
dissent, it is the sick patient who “embod[ies] only the correlation between 
homocysteine and vitamin deficiency,” Lab. Corp., 548 U.S. at 137, not the claimed 
process. 
From the standpoint of policy, the Lab Corp. dissent avoids the same 
fundamental question that the Federal Circuit does not ask or answer today:  Is this 
entire field of subject matter undeserving of incentives for invention?  If so, why?  In the 
context of Lab. Corp. that question is very telling:  the natural condition diagnosed by 
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