Switch to a string comparison instead of a numerical comparison and it'll work. Didn't you notice all the "Argument isn't numeric in numeric ne (!=)" warnings?

my @allcompanies = qw(
   Acme
   Google
   Yahoo
);

my $to_remove = 'Acme';

my @selectcompanies = grep { $_ ne $to_remove } @allcompanies;

print(join(', ', @selectcompanies), "\n");  # Google, Yahoo
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