This look at Wayne Thiebaud's market—based upon data from our friends at Pi-eX—is available to AMMpro subscribers. Monthly subscriptions begin with the first month free. Feel free to subscribe and cancel before you are billed.

Barney Ebsworth's art collection is going to light up the November sales this year bringing some extraordinary examples of American Modern and Contemporary art to the market. Yet for all of the excitement that will surround the sale, one lot bought by Ebsworth for an astonishing and record price in 1997 will be missing. It hasn't been sold privately; it won't appear in a later auction; it hasn't been donated to a museum; it appears to be work Ebsworth's heirs are attached to.

With an overall value targeted around $300m, Ebsworth's collection doesn't need Wayne Thiebaud's 1962 Bakery Counter — which could easily carry a $20-25m estimate — to generate a significant fortune. Ebsworth's heirs won't feel a loss but the Contemporary art market might.

The art market thrives when an artist with a substantial body of work sees a broad increase in value. This process is often provoked by redefining the sale of a particularly good, sought-after and impressive work of art. The markets for Rothko, Richter, Basquiat, de Kooning  and many others were similary transformed by the sale of single exemplary work.

We used to use the term masterpiece to describe these types of works. It would not be out of line to call Bakery Counter Thiebaud's masterpiece. This post will look at the last 12 years of Thiebaud's auction sales. Before we get there, though, it is worth recounting some of the sales history of Theibaud's great work.

A good deal of the appeal of Bakery Counter lies in its substantial size, early date and the fact that the image depicts Thiebaud's echt subject matter, cakes and pastries. The artist's work is far broader than that. Nonetheless, the painter's taste for sweets sits at the confluence of art history and popular appeal.

One reason Thiebaud's market has lagged many of his peers is the fact that his work was long considered regional or of minor interest. It took until 2001, when the artist was 80 years old, for the Whitney's retrospective of that year to have an impact upon his reputation in the wider art world.