I was looking at peoples book shelfs in the bazaar and someone has the same book but one is listed as mass market paperback and ones says paperback?   I thought they were the same?

I think it refers to size. Mass Market tends to be those little ones you see at the grocery store, where as just paperback is more like what you see at the bookstore and is a little bit larger.

When it just says paperback, this can mean either trade sized, the taller size, or mass market sized . It does not specify which size.

This really has to do with the publisher. Some use one ISBN for various sizes. Some use separate numbers for each size. 

So  paperback could be the Trade size?

yes, paperback can be any size at all.

if the listing specifically says "mass market paperback" that's the smallest one, but in terms of PBS rules, any size paperback (provided it's same ISBN of course) could be posted to a listing that says "mass market paperback".

If I really care, I check Amazon to see if there is different sizes of the paperback and whether or not they have different ISBNs.

Yes. This really is a question of the publisher's choice. They pay for each ISBN. But they might also inventory by the ISBN. So different numbers could help with inventory and sales tracking. Some publishers will also use a specific number for different retail locations, such as a religious sales or book club sales. 

The type of paperback, or general paperback, is entered on PBS on the first listing of the book. This is often based on how the publisher is listing the size. This data is incredibly hard to change in our database. 

but in terms of PBS rules, any size paperback (provided it's same ISBN of course) could be posted to a listing that says "mass market paperback"

As far as I know, if it specifies the type of paperback then your book must match. So, you cannot post a trade paperback to a listing that specifically says mass market or a mass market to a listing that specifically says trade paperback (although I don't think I've ever seen one like this).

If it says "mass market paperback" your book must be mass market size. If the listing just says "paperback" it can be any size paperback.

This is how I've always interpreted the binding rule. I'll look around and see if something else was said by the team.

Thanks everyone!

Thanks everyone!

I do not read mmpb books so when I order a book in Games and it says just paperback, I check with Amazon to see what size it is.  If the isbn says Trade Paperbook, then I know I can order it in the Game swap.

okay !

As far as I know, if it specifies the type of paperback then your book must match.

The rules do not say that anywhere.

If that's a rule, then PBS should probably put it in the rules.

Sara - Mass Market Paperback is a specific type of binding. Binding must match, this is one of the requirements when posting a book. 

I looked and couldn't find anything saying it was okay to post a trade paperback to a mass market paperback listing.

This has always been my understanding of the binding rule. I will send a message to the team to check.

Yes, this would be an interesting clarification.  Guidelines are firm about binding....ie, paperback vs.  hardcover.  But I've also not seen anything conclusive within each of those catagories.

So , a paper back can be any size? 

Lisa, if the listing says "paperback" for book type then the size/type of paperback doesn't matter as long as all other criteria are met

Yes, I even have some very large children's books that are listed as paperback.  So they really can be any size.

I heard back from the team. I was wrong, sorry.

as long as everything (title, isbn, author, paperback) matches it doesn't matter if the listing says just paperback or mass market paperback. It's not that specific. Apparently I was reading way too much into it. Sorry everyone, sometimes I have a habit of being overly cautious.

I don't think it's really likely that you'll get a trade size listed as mass market - I've never seen it. If it does happen and you're worried about it not being exactly the same send in feedback with the info and they will change I from "mass market paperback" to just "paperback"

That's what I thought ... but thanks for confirming it!!!!