What does "thanks x-institute for hospitality" mean in an acknowledgement? What does 


  The author wishes to thank institute X for hospitality. 


mean in an acknowledgement?

Does it imply that they paid me a hotel or a per diem, or is it enough if they provided me an office during my visit to motivate that statement?  

Edit. I was just worried if this could rather interpreted as the institute X paid me, which in other country could be seen as a double funding (which is in some programs not allowed).
Usually it means that, during at least part of the preparation of the paper, the author was on an extended visit to Institute X, and X provided something that was helpful.  It could be as little as an office or a library card, or as much as free housing, use of expensive equipment, travel support, etc.  However, this phrase wouldn't normally be used if the author was actually a paid employee of X during that time, even if temporarily.