Analyzing insider buying and selling is a great tool to help round out an investment thesis and tip the needle toward a buy or a sell. However, all buying and selling is not created equal. Motley Fool Pro Analyst Bryan Hinmon talks about how piggybacking open market acquisitions by insiders can be a wise move.

Over the past six months, activist investor and board member Nelson Peltz spent $80 million bolstering his position in asset manager Legg Mason (NYSE: LM). Now owning nearly 7%, Peltz is looking to create value by engaging in "operational activism" -- a nice way of saying he wants to reinvigorate the Legg Mason brand and get rid of businesses that are a distraction. Based on his previous wins at H.J. Heinz and Wendy's/Arby's Group, piggybacking Peltz's sizable purchases could be a win for Legg Mason shareholders.

Not all insider transactions are by activist board members, of course. Other insiders at solid companies are engaging in significant open market acquisitions, too. Two that warrant further investigation are Chief Financial Officer Michael Angelakis' purchase of Comcast (Nasdaq: CMCSA) shares and new director Antonio Monteiro de Castro's foray into Tupperware (NYSE: TUP). Watch the video here:

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