It may sound weird, but there is not a link between lending from libraries and book sales. Some children’s books sell well, but if you go to the sections of them in book stores you’ll rarely find more than a handful of Danish authors represented. The ones which the bookstores know will sell well.

Our Libraries have to make all Danish published material available. Some of this is indeed not bought, but because children’s books are often on the high end of popularity at libraries they generally by every children’s book which gets published buy one of our major publishers. Also, publishers often lobby the municipality politicians who set the overall guidelines for their local libraries to make sure their books are represented.

Are you referring to https://www.retsinformation.dk/eli/lta/2004/1439 ?

Out of curiosity, can you provide some examples of these books which are artificially expensive, popular in libraries, but not for sale commercially?

> Also, publishers often lobby the municipality politicians who set the overall guidelines for their local libraries to make sure their books are represented.

Politicians are supposed to set the overall guidelines but not to decide what individial books libraries purchase. Do you have examples where politicians pressure or force libraries to buy specific books?

So, can I publish a book in Denmark, say it costs 1,000 dollars, and your libraries will be forced to buy it just because they have to make "all Danish published material available."?? There must be some sort of guidelines (though seeing how Swedish law works I wouldn't be surprised you guys just "trust" people to price things correctly).

All publishers are required to supply one copy of any published book to the royal library (for free).

Individual libraries are not required to buy any particular book. They have a fixed budget for buying material and will decid based on quality and expected demand.