Best 2011 penny stocks?

Not financial advice: The Securities and Exchange Commission defines a penny stock as being valued at less than $5 per share.

The top 5 most successful 2011 penny stocks from the NASDAQ, NYSE, and NYSE Amex exchanges, by percentage gain from January 1-December 31, were:

TeamStaff, Inc. (NASDAQ:TSTF) +271% from $0.50 to $1.89
Merus Labs International, Inc. (NASDAQ:MSLI) +120.93% from $0.86 to $1.90
Authentidate Holding Corp. (NASDAQ:ADAT) +51.11% from $0.46 to $0.68
Samson Oil & Gas Limited (NYSEAMEX:SSN) +47.73% from $1.36 to $1.95
Synthesis Energy Systems, Inc. (NASDAQ:SYMX) +32.48% from $1.17 to $1.55

This does not include OTC/OTCBB or Pink Sheet stocks. These are stocks that do not meet listing requirements for major exchanges. Such companies can be very small and/or very unstable and as such are considered extremely risky investments. They also may trade infrequently, meaning that there isn’t always a buyer when a shareholder wants to sell their stock.

Belonging to a major exchange doesn’t necessarily insure more stability. On May 18, 2012 Facebook went public (NASDAQ:FB). Even though they were on the NASDAQ exchange, the IPO has gained allegations of mishandled buyer’s/seller’s orders and insider trading of overvalued shares.