Constant data upload by NIS

I've experienced a problem with my mac constantly uploading data (my monthly internet upload quota was exceeded).  My mac runs NIS 5 & being suspicious of malware I run a full system scan with no issues identified.  To help me determine what was uploading data, I bought a program “Little Snitch”.  To my amazement the application is “symdeepsight-extractor” which is uploading data to the server “upload3.symantec.com”  I find it hard to believe that it was necessary for Symantec to collect 1.7Gig of data from my mac.  Has anyone else had this issue?  Does Symantec have a comment on what data they are collecting off my system?  I have now used Little Snitch to block this traffic.