One very well documented case is the British sculptor, Dame Barbara
Hepworth, who repudiated all her (perfectly authentic) work of the late 
1920s, and established a "catalogue no. 1" "recognised" baseline in (from
distant memory) around 1930.  About 15 years ago I had some correspondence
on this with Sir Alan Bowness (former Director of the Tate Gallery and
Barbara's son-in-law) on the details when an uncatalogued piece of around
1927 appeared in a London auction.  At his request, respecting her wishes,
we did not bid for the sculpture.  No doubt you could contact Alan for
further details via the Henry Moore Trust.

There are of course many (apocryphal?) stories of artists who
"authenticated" works if they still liked them and condemned them as fakes
if they did not. 

Patrick Boylan

=========================

On Mon, 1 Sep 1997, Paul Messier wrote:

> Subject: Artists disowning their art
> Newsgroups:   bit.listserv.museum-l
> 
> For a paper I am writing on the preservation of media art, I’m looking
> at issues relating to involving artists in the conservation &
> restoration of their own art.  I am particularly interested in instances
> where artists have "disowned" work which was restored without their
> direct involvement.  Replies on and off the list would be appreciated.
> Thank you.
> 
> --
> Paul A. Messier
> Conservator of Photographs & Works on Paper
> Boston Art Conservation
> http://www.bosartconserv.com
>