You need to escape the forward-slash only if this character is used as the regex delimiter character.

c:\@Work\Perl\monks>perl -wMstrict -le
"$_ = '/foo/bar/baz/bat';
 print qq{'$1'} if /([^/]+)$/;
"
Unmatched [ in regex; marked by <-- HERE in m/([ <-- HERE ^/ at ...

c:\@Work\Perl\monks>perl -wMstrict -le
"$_ = '/foo/bar/baz/bat';
 print qq{'$1'} if m{([^/]+)$};
"
'bat'
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