Ryan Calo, CIS Director of Privacy and Robotics, is quoted by Ameet Sachdev in the Chicago Tribune on the surprising type of protection e-mail disclaimers actually offer the sender.

The other day I received an email from a lawyer in Chicago who I don't talk to very often. So I was a little surprised to hear from him.

There was nothing in the body of the email, but there was an attachment that I proceeded to open.

It didn't take me long to realize that I was not the intended recipient. The attachment was a confidential memo that discussed a possible transaction. Handwritten notes were sprinkled throughout the typed memo, and it was clear from the email's subject line that the lawyer had written the notes.

I sat back in my chair, stunned. I had no doubt that the disclosure to me was inadvertent. Other recipients included lawyers at the firm. A closer look at the email showed it was sent by the lawyer's secretary on his behalf.

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An interview with Ryan Calo at the Center for Internet and Society at Stanford Law School reinforced Brown's conclusions. Calo added that the disclaimers do have value if they make unintended recipients think twice.