Mad Mail: Ebix, Micromet, SIGA Technologies and More

Cramer may have 31 years of experience in the stock market, but he still gets stumped on stocks from time to time.

Even with 31 years of experience in the stock market, Cramer gets stumped on stocks from time to time. After all, you can't know everything. You can, however, do your homework. So after researching the names he wasn't familiar with, Cramer gave his calls on Friday's "Mad Mail."

Last week, Shelly in Illinois asked Cramer about Ebix . The Atlanta-based company provides software and e-commerce solutions for the insurance industry. Cramer thinks it could be a lucrative business consider U.S. insurance companies spend $60 billion a year on a very fragmented information technology infrastructure. While Cramer thinks Ebix's company looks solid, he's not a fan of the stock. It fell nearly 25 percent last week following a news report that criticized the company. The company held an investor conference on Friday to outline its plan and announced a $45 million buyback. Still, Cramer doesn't recommend getting involved in what seems to be a messy situation, especially when there are other names to invest in.

Last Tuesday, Marco in New York wanted Cramer's thoughts on Micromet . After doing some research, Cramer thinks this biotech company has no profits and hardly any revenues. It's a speculative stock and Cramer wouldn't invest in it right now.

On Thursday, Cramer took a call from Zak in Connecticut, who asked about SIGA Technologies . The bio-defense drug development company makes countermeasures against potential agents of biological warfare. It's smallpox treatment is currently undergoing a safety trial and is expected to seek approval from the U.S. Food and Drug Administration next year. The driver for the stock, however, is a $2.8 billion federal contract for smallpox countermeasures that's expected to be awarded in the first-half of this year. If SIGA gets the contract, Cramer thinks shares will soar. The company is also involved in litigation over the ownership of the smallpox vaccine with a resolution expected around mid-year. With that in mind, Cramer doesn't like the risk-reward and would pass on this stock.

The next letter came from Greg, who asked if Briggs & Stratton would be a good play on the Japanese reconstruction. Cramer recommends sticking with his faves Caterpillar and Cummins .

Alan wanted Cramer's thoughts on silver. Cramer blessed the trade and recommends investing in the exchange-traded fund.

Finally, Jim wanted to know what's happening with Ford Motor . Cramer said this stock has been in the doghouse for a long time, but could soon take off. He likes the management style of CEO Alan Mulally.

When this story was published, Cramer's charitable trust owned Caterpillar and Cummins.

Call Cramer: 1-800-743-CNBC

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