I'm not discounting the fact that something strange might be going on here, but I must first suggest that you output the SQL statement that you are passing to SQL Server directly on the webpage from which it is being executed. Specifically, put an unusual character around the statement so that you can see whether or not there is a SPACE character before the last percent sign.
It could simply be a matter of not trimming the var that holds "Some Company".
This will return zero records:
select * from table where Customer LIKE '%Some Company %'
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