Prosper filed a S-1 Registration Statement with the Securities and Exchange Commission (SEC) today. The document can be read here.
Recent related history
This week: Prosper fined $1 million; class action lawsuit prepared
Last week: SEC files cease and desist against Prosper; Loanio halts operations
Oct 15: Prosper halts operations; enters quiet period
Oct 14: Lending Club emerges from quiet period
Oct 9: Zopa closes
Oct 1: Loanio opens
April 2008: Lending Club enters quiet period