Text::Balanced handles this nicely. 
use strict;
use warnings;
use Text::Balanced qw(extract_bracketed);
my $text = '(aaa) (bbb (ccc( ddd) eee) (fff)' ;
my @tokens = extract_bracketed($text, '()');
print "$_\n" for @tokens;

# Output:
#(aaa)
# (bbb (ccc( ddd) eee) (fff)

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In reply to Re: regex to parse (nested) parenthesis delimited string? by imp
in thread regex to parse (nested) parenthesis delimited string? by varian

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