Who designed it first ?  

Borge Mogensen (BM1160 "Huntsman's" table 1950).

interesting. So rank may be:

1950 Borge Mogensen

1953 Hans Wegner

1956 (?) Hvidt

These guys didn't work in a vacuum. Most if not all of the greats were influenced (consciously or otherwise) by others' previous work and the examples noted above are all great designs regardless, in my humble opinion.

Meaningless here of course, but I did see one source list the Hvidt desk as from 1954.

Interesting; I agree these are nice desks. For some reasons, the one from Wegner I like it the most. Both Mogensen and Wegner are still produced these days, but there is a substantial price difference between the two. Cheers

I don't think that any of the three invented this design. Regarding the price: Althouh they look similar, they are all structurally completely different pieces. The CH table and the Soborg table were designed for production on an industrial scale. The JH table was a high end cabinetmaker piece whicht required and still requires a lot of handwork. 

I wander why for the Soborg table the brass metal pole were not preferred over teak wood.