design ownership  

First, I don't know the legal answer...
but the bundle of rights in a good can be complicated. If A owns a Wright house, A can sell it or the furniture inside it without paying a royalty to the Wright estate for conveyance of ownership, as far as I've heard.
A can also rent the house and furniture out, or even charge admission for touring a Wright house.
The question of whether someone could copy the Wright furniture in a Wright house and market the copy commercially would, I believe, depend on whether Wright's architect's fees contract explictly stated that he retained sole right to duplicate the design of the house, the furniture, etc., or not. Another possiblity would be that the estate more recently has laid legal claim to some of the designs, but who knows. If not, then I would say it would be worth paying a competant attorney a few hundred dollars for an opinion before charging into copying some of Wright's incredibly uncomfortable home furnishings.
Sorry, I can't be of more help.

On DA you get it for free...
All possible legal intellectual property protection or rights on FLR's furniture are expired. So go ahead. The owner of the house or furniture has no particular rights with the exception of the copyright on pictures that he or she might have taken. That's why you are not allowed to take pictures in most museums because you would than own the copyright on that picture of say... the Mona Lisa. The only thing that you can not do is using the FLR name in connection with your copy because I suspect that someone has copyrighted the name and a copyright (in most countries) extends way beyond the dead of the author.The most legal way is always to be honest about what you are doing so you can say: this is a copy made by xyz according to original drawings from FLR, or measurements taken in the home of...etc.

Alright!
That's decisive enough for me.

Thanks for the insight...I...
Thanks for the insight...I am the owner of the house that the furniture originally was designed for. The furniture is now in the hands of private collectors. I have the prints of the furniture and was worried that if they got into the "wrong" hands that copies (of the furniture) could be made without my consent, if in fact the consent was mine to give. Or, if the rights of the design transfered to the current owner of the custom furniture. Or, if there were no rights to begin with:) I was using FLW as an example...it could be any designer, laszlo, Mies, Eames, etc...

If you own the prints...
put them in a safe and use only reproductions on which you cleam copyright. (the c in a circle, plus the year and your name) It does not transfer the rights of the original design, but it gives you the copyrights on the reproduction and considering that the original is not available anybody who wants to use the drawings has to use your reproduction. As said before this is how museums and collectors can hold on to copyrights or century old art in spite of the fact that no other copyrights apply. Each time the copyright expires you make a new picture, and you are good for another century or so.