Technically speaking, both CC’d and CC’ed are incorrect. These are slang terms for saying you “carbon copied” other people in something like an email. But, both are becoming a more frequent and short way for people to convey the past tense of the verb “carbon copy.”
The internet and the language people use have shifted the English language in many ways. Because of this, there’s a big debate over whether people should use CC’d/CC’ed or not.
More traditionalists believe people should avoid making non-existent contractions because it further contributes to lowered intelligence in speaking and writing. On the other end, however, people don’t think much about it and use them all the same.
Past; Present of Carbon Copy
Before the introduction of photocopy machines, there was a thing called carbon copy. This is a thin cellophane sheet that people would place between leaves of paper. When they would write on the surface of the outermost sheet, it would also transfer to the sheets below it.
But, this was a huge use of resources that also created copious amounts of waste. Therefore, when photocopiers came into the picture, it removed the need to continue using carbon copies. While they were and are still around, their popularity waned greatly.
Then the innovation of email, the internet, and online communications came to be. In this context, CC is the recipient line in an email platform. It allows secondary people to see each other’s addresses along with the person who originally sent the email.
This is what people are referring to when they used either CC’d or CC’ed. They’re saying that they carbon copied others in something like an email. Very rarely will you ever hear it for an actual carbon copy used to create duplicates of a document as you would have in the 1940s.
I carbon copied you in the email yesterday because it’s important that everyone receives the notification.
I CC’d you in the email yesterday because it’s important that everyone receives the notification.
I CC’ed you in the email yesterday because it’s important that everyone receives the notification.
In our high-tech age, using both CC’d or CC’ed is acceptable. But, it’s also just as important to acknowledge that using either isn’t particularly proper English. It turns a verb into a contraction that simply doesn’t exist.