Untested: 
$data = join " ", $data =~ /\b[A-Z][a-z]*\b/g;

[download]
This assumes you don't have accented letters (nor non-Western letters), and it may not do what you want for words like "Don't" and "O'Hara".

In reply to Re: Help composing Regex for matching only Titlecase words by JavaFan
in thread Help composing Regex for matching only Titlecase words by seand

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