This post is one in a series in which more than 60 newsletter advisors share their Top Stock Picks for 2011. This special report is courtesy of TheStockAdvisors.com.

"Last year for my favorite stock pick, I recommended IMAX which more than doubled; this year I would like to recommend Siga Technologies (SIGA), which I believe offers the same kind of upside potential for 2011," says Dennis Slothower. Dennis's Top Pick in last year's report rose 99%.

The editor of Stealth Stocks explains, "Siga is a bio-defense company. In 2004, the U.S. started an initiative called Project BioShield, which gave the government the right to purchase and stockpile vaccines and drugs to fight anthrax, smallpox and other potential agents of bio-terror.

This post is part of a special annual report -- Top Stock Picks '09 -- in which TheStockAdvisors.com asked 75 leading newsletter advisors to select their favorite investment for the new year.

"Emergent BioSolutions (NYSE: EBS) -- my top 2009 pick -- makes the only FDA-licensed vaccine for the prevention of anthrax," says Timothy Lutts in his The Cabot Stock of the Month.

"Located in Rockville, Maryland, the company is currently filling a $448 million government order for 18.75 million doses, and in October, the U.S. government contracted to purchase 14.5 million additional doses valued at up to $404 million, to add to the Strategic National Stockpile.

"The vaccine is named BioThrax, and it accounts for 97% of the revenues of Emergent BioSolutions. However, the company has a full pipeline including two 'next generation' anthrax vaccines.

"Also in development are two anthrax therapeutics (immunoglobulin and monoclonal), two botulinum vaccines and a botulinum therapeutic (botulinum is the nasty form of Botox), an oral typhoid vaccine, a next generation tuberculosis vaccine, a hepatitis B immunotherapy and a chlamydia vaccine.