10:42 AM PT -- Clements Design Inc. -- Kim's go-to design team -- tells TMZ ... "This issue was brought to our attention over a year ago. We communicated with the Judd Foundation’s counsel and explained to them in no uncertain terms that there were obvious key differences between the tables and chairs in Kim’s office and the Judd Foundation’s tables and chairs."

They add, "The Judd Foundation’s prior counsel acknowledged these differences and since then, we have not heard from them in over a year, and are now being blindsided with a lawsuit. Efforts were made to resolve this issue amicably at the time and the Judd Foundation was unwilling to settle on reasonable terms. These claims have absolutely no merit."

Kim Kardashian is being sued by the estate of a renowned artist, which claims she promoted a bunch of furniture she claims he made ... but none of it was his.

The Estate of Donald Judd -- an artist famous for sculptures and uniquely designed pieces, including furniture -- alleges a video Kim posted in 2022 where she gave a tour of her SKKN office ... highlighted a table and a set of chairs she bragged were Judd originals.

According to the docs, obtained by TMZ, the Estate claims Kim got this furniture from a company called Clements Design -- also a defendant -- but it's unclear if Kim knew the pieces weren't the real deal.

Unfortunately for Kim, the Estate claims these items were knockoffs, and because Kim touted them as the real McCoy ... it led people and media outlets to think that the pieces were designed by Judd.

The Estate says because of the publicity her video got, it's tarnished Judd's reputation and legacy.

The Estate wants Kim to take the video down, retract her claims the furniture was Judd originals, and they want profits from Clements Design.

We reached out to Kim's rep ... so far, no word back.