It's got no known abiotic process for being generated, but a clearly understood connection to life, and is apparently very reactive and would have to be actively re-generated at mass scale to sustainably show up in an atmosphere.

Nothing should be taken as proven, but it feels staggeringly plausible, and in my opinion would be the biggest of the "big if true" space stories I've ever seen in my lifetime.

At one point in this fascinating talk, she mentions that aliens would immediately be able to identify Earth as inhabited by life, because only a stupid and yet advanced civilization would be capable of creating CFCs. I highly recommend this video.

[0] https://youtu.be/iN0uyGVNlkQ?si=unBC3Cj228fKJV4i