Web shoppers love auctions. But if you want to use auction sites to buy software, you may want to think again: it's almost certain that the software you're bidding on is pirated.

In a study released this month, the Software & Information Industry Association (SIIA) stated that 91% of software sold through online auction websites is pirated.

For a purchase like software, you're better off sticking with traditional purchase methods.

But if you can't stay away from auctions, consider these tips from the SIIA before submitting your final bid.

• Red flag terms. The terms "backup," "CD-R," "compilation CD," "OEM," "academic," and "not for resale," are clear signs that software offered for auction is illegitimate.

• Losers still win. After losing an auction, an email from the seller offering another copy at the losing bid usually indicates illegitimate software.

• No manuals or licenses. Terms of software licenses specify that all components accompanying the product must be provided if legitimately resold. Software that does not come with manuals or offers online manuals is almost always illegitimate.

• Not enough info. What an auction doesn't say is often as important as what's said. A link to the publisher's site may be helpful in selecting products, but it provides no indication of validity. Consumers who want to bid on software with no descriptions should consider alternative auctions.

• Look familiar? Be wary of multiple auctions that look the same, even if the seller name is different. Pirates usually have several concurrent auctions -- sometimes offering the software and manuals in different auctions. Regardless, this is usually a clear sign of one individual burning copies and making a living by selling illegitimate goods.

Amazon's all right

Take note: According to the SIIA's study, Amazon.com Auctions, which proactively monitors auctions and removes those offering illegitimate goods, had almost no illegitimate software available on the site.