The phone number 1-800-ITS-UNIX, didn't help.  But ATT sued the Regents of California first because of UCBs net releases. And while there were many of the same principles, the two lawsuits were different.

At&t did not have much choice. Unix was protected by trade secret, and once it was available, the trade secret was gone. Rick Adams asked a lawyer if somebody posted it to Usenet by uploading it from a phone booth. Would happen, The lawyers gulped and said it's available now.