Amazon is a gold mine of data for advertisers, according to Pacific Crest Securities analyst Chad Bartley.

"The industry contacts we've talked to in the last few months have indicated that they are the sleeping giant—they are the juggernaut in the industry" said Bartley on CNBC's "Fast Money" on Monday.

"They're sitting on very valuable consumer data in terms of how they shop, what they look for and most importantly, what they buy on Amazon. So I think that for a lot of advertisers and marketers that transaction data could be very, very valuable for targeted advertising."

Pacific Crest estimates that the ad business will grow 45 percent in 2014 and could yield $4.4 billion in revenue by 2018.