A look at the weighted underlying holdings of the Lux Nanotech Portfolio (PXN) shows an impressive 14.1% 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 BioDelivery Sciences International Inc (BDSI), which makes up 4.46% of the Lux Nanotech Portfolio (PXN), has seen 2 directors and officers purchase shares in the past six months, according to the recent Form 4 data.