Length of focus given by new patent is not a name (9,4)
I believe the answer is:
attention span
'length of focus given' is the definition.
The definition suggests a singular noun which matches the answer.
'new patent is not a name' is the wordplay.
'new' indicates an anagram.
'name' becomes 'n' (common abbreviation e.g. on forms).
'patent'+'is'+'not'='patentisnot'
'patentisnot' is an anagram of 'attentionsp'.
'attentionsp'+'a'+'n'='ATTENTION SPAN'
'by' is the link.
Can you help me to learn more?
(Other definitions for attention span that I've seen before include "criticism, if it's much shorter than necessary" , "Time to concentrate" , "Length of time for concentrating" , "Concentration period" , "How much does one heed" .)