I'm organizing a complaint to the US Patent and Trademark Office which says that Lockheed Martin (NYSE: LMT) shouldn't be granted a trademark for "Cyber Kill Chain" because it is in common usage. As I wrote earlier, I was surprised that they even filed for a trademark since I was the one who first coined the term (as far as I can tell), but coinage of the phrase isn't enough to defeat Lockheed Martin's attempt to trademark and build a business around it. Common usage, however, is an argument that the US PTO will listen to, especially if we can show a good number of people objecting to its registration.
If you wish to have your name added to my US PTO complaint, please send me an email to that effect. It should include your contact information, how often you've used the phrase, and your objection to LMT's trademarking of it.