Recently I was in the emergency room. I asked for a work note and was given one with the date and time I was seen when I could return to work and my diagnosis. My employer attempted to verify this note and called the ER where I was seen. They gave him the same information that was on the note. Is this a HIPPA violation?

Nope. Since you volunteered the information by giving them the note, you authorized the ER to release the info.