it can get confusing with our new listing codes, but Wayne explained it perfectly. Its most likely a short sale that has an offer, but until the bank/creditors accept the reduced amount of the short sale, its technically not "pending". You might still be able to make a backup offer, depending how the seller wants to do it. Your agent can help you find out if they're taking backup offers. Just fyi, pending short sales are great ones to have a backup on, because they fall apart for many reasons and you could slide into first position if you hang on. Usually its because they take so long, and buyers think they can wait but often can't. Then as the backup offer, you have a chance to get it. If you don't have an experienced short sale agent, I would highly recommend you find someone that's sold them before. That helps you understand the process better and know how to react, but it also helps the transaction come together successfully, as they are not a normal transaction.
By the way, I've sold many short sale listings, in fact 2 closed in August. I would be happy to help if you need an experienced agent! Short sales can be filled with disappointment and frustration, but if you can hang in there, you may get a property for as much as 10-15% under market. Its not for everyone, though, and I'd be happy to discuss your goals with you, and let you know the pros and cons of buying a short sale.
Best to you,