Lehman Brothers' Principal Protected Notes (PPN) were recommended as safe income-producing investments. Brokers at UBS and other firms pitched these products as similar to buying a basket of stocks (such as the S&P 500) but with the added benefit of up to 100% principal protection if the market went down. However, Lehman Brothers declared bankruptcy in September 2008.

Retail customers who bought the Lehman Brothers' PPN's suddenly had no principal protection, did not own a basket of stocks, and were holding worthless pieces of paper. Chastising UBS, one government regulator recently said, "UBS presented these notes as simple, safe investments when in fact they are highly volatile and are subject to shifting market conditions."