After thinking a bit more about this, the following approach using look-around assertion works:

use warnings;
use strict;

while (<DATA>){
    my @matches;
    @matches = (/(?<=[%>])%([^%]+)%(?=[%<])/g);
    print join ' ', @matches;
    print "\n";
}

__DATA__
<span color="#231f20" someattr="%do_not_match%" textOverprint="false">
+%PN1%</span>
<span color="#231f20" someattr="%do_not_match%" textOverprint="false">
+%DIMMM%%DIMINCH%</span>

__END__
PN1
DIMMM DIMINCH

[download]

In reply to Re^3: Trouble capturing multiple groupings in regex by Corion
in thread Trouble capturing multiple groupings in regex by reverendphil

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