A look at the weighted underlying holdings of the Zacks Micro Cap Portfolio (PZI) shows an impressive 16.1% of holdings on a weighted basis have experienced insider buying within the past six months. Start slideshow:10 ETFs With Stocks That Insiders Are Buying Arbor Realty Trust Inc (ABR), which makes up 0.28% of the Zacks Micro Cap Portfolio (PZI), has seen 3 directors and officers purchase shares in the past six months, according to the recent Form 4 data.