Here is a regular expression I created to identify Capitalized and ALLCAPS alphanumeric words that are not at the start of a sentence which may indicate they are proper names aka a pronoun. It uses a lookbehind ?<=
to avoid matching words at the start of a sentence.
(?<=[\w,:;-])\s+([A-Z0-9]+[A-Za-z][A-Za-z0-9]*)\b
See it working at the handy website Regex101 - https://regex101.com/r/5haqtp/2