One of the lawyers chasing the assets of jailed Ponzi king Bernard Madoff remembers a day four years ago when he didn't know who Madoff was.

David Sheehan has spent nearly every day since trying to recover as much as possible of the $17.5 billion in losses calculated since Madoff was arrested on Dec. 11, 2008.

He's the chief counsel for the trustee tasked with recovering the losses. They have secured nearly $9.3 billion so far and hope to collect at least $3 billion more.

If all goes as planned, he says the losses will be cut to around $5 billion of the original amounts thousands of investors put into Madoff's sham investment business.

Sheehan says it's more than they thought possible when they started four years ago.