The OP does not include USA or UN as example text. Mine also gives results that are likely undesirable for character sequences that contain numbers or punctuation. Yours is likely no better on that front, though you did provide a disclaimer. Development of any regular expression depends strongly on what you are going to feed it - I think mine has the advantage of outputting more junk that yours would, making its weaknesses more obvious once the OP started putting it into practice.

In reply to Re^3: Help composing Regex for matching only Titlecase words by kennethk
in thread Help composing Regex for matching only Titlecase words by seand

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