Adobe: How did they do that?

[Bosco]

I'm using CS6 at work. Someone recently sent us a file that was created in CC (it won't open in CS6).

I went to the Adobe website to download a trial version of CC. I created a yahoo email account before signing up. After it finished downloading, a message prompted me to check my email to authenticate. The message had my home email address listed, not the yahoo one I created just for this download.

How does Adobe know my home email address and how would they get it if I used the yahoo address to sign up?

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