I'm guessing that right now the code (you haven't posted any, so the best I can do is guess!) in the Char handler is saving a reference to the last bit of character data, and then when the End handler sees the end of the Title element, it does something with that. Maybe something like this:

use 5.010;
use strict;
use warnings;

use XML::Parser;

my ($got_title, $in_title);
my $parser = XML::Parser->new(
    Handlers => {
        Start => sub { $in_title++ if $_[1] eq 'Title' },
        End   => sub { $in_title--, say "GOT TITLE: $got_title" if $_[
+1] eq 'Title' },
        Char  => sub { $got_title = $_[1] if $in_title },
    },
);

$parser->parse(<<'XML');
<Document>
    <Title>Company A&amp;B Information</Title>
    <Abstract>Foo</Abstract>
    <Title>Company X&amp;Y Information</Title>
    <Abstract>Bar</Abstract>
</Document>
XML
[download]

Instead you want the Char handler to accumulate the pieces of character data using either string appending, or pushing onto an array/arrayref, then use the Start and End handlers to signal when to start and end accumulating character data. For example:

use 5.010;
use strict;
use warnings;

use XML::Parser;

my (@got_title, $in_title);
my $parser = XML::Parser->new(
    Handlers => {
        Start => sub { $in_title++, @got_title = () if $_[1] eq 'Title
+' },
        End   => sub { $in_title--, say "GOT TITLE: @got_title" if $_[
+1] eq 'Title';  },
        Char  => sub { push @got_title, $_[1] if $in_title },
    },
);

$parser->parse(<<'XML');
<Document>
    <Title>Company A&amp;B Information</Title>
    <Abstract>Foo</Abstract>
    <Title>Company X&amp;Y Information</Title>
    <Abstract>Bar</Abstract>
</Document>
XML
[download]

Thank you! This is exactly the type of bug fix I will be implementing in my code. All makes sense now.