I'm now in touch with one of the guys at Heritage and have sent him a mail where I give my arguments.
Here's part of what I wrote. (To sum it up for those of you not having read the previous posts.)
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Let me give you my arguments why I don't believe this to be the work of Barks.
But first of all let me make a note about the 1974 painting of Scrooge.
The original source for the info about a 1974 ”Uncle Scrooge portrait” comes from a letter Carl wrote to Matti Eronen in 1992:
"This small painting is an "unknown". I did it in 1974 and gave it to somebody. I kept no record of it in my files, and have only one small photo of it. I think it is 10" x 8", and that I gave it to […].”
It has since seen print and is called "The Tycoon". We printed it on page 182 in "Carl Barks Målningar och teckningar".
It's not the one you have at auction.
Now, with "The Tycoon" painting out of the picture what do we have here?
A painting with the exact dimensions as the 1975 painting "Oh, Oh!"
It's interesting to note that he 1975 painting wasn't available as a good repro when the fine arts book was made and still wasn't in 2011 when we did our book.
It wasn't until October 7 this year that a slide of the painting (from the Barks Estate) turned up in Denmark.
It's also interesting to note that the painting up for auction looks more similar to the previously printed image than the image on the slide.
To me that's an indication that someone might have used the printed image to do his/her own version of a Barks painting.
But that's of course just speculations.
Here you can see the three images side by side: http://2.bp.blogspot.com/-3YW2KxMy-Uk/VhgGNyAWbWI/AAAAAAAAJJQ/Lk_iLEfia5k/s1600/Ska%25CC%2588rmavbild%2B2015-10-07%2Bkl.%2B20.00.40.png
Let's take a closer look at the painting.
Compare the images. The one to the right show how Barks handled drawing beaks etc.
http://1.bp.blogspot.com/-RyAQ-s9IKc0/VhgFiFZyCOI/AAAAAAAAJJA/usu5m_umUbo/s1600/Close%2Bup%2Bcompare.tif
The highlights on the painting you have suggests that the painting is finished, but at the same time the scratchy lines suggests that it’s not.
Look at the use of unblended colors like the white highlights, the blue on Scroooge’s glasses and the black on the beak.
Barks would have used blended colors like the old masters.
Follow this link to see what I mean:
http://1.bp.blogspot.com/--fbunmfLURY/VhgFqUrFojI/AAAAAAAAJJI/_Ex-T3amTJI/s1600/Close%2Bup%2Bnotes.jpg
I have never seen color been used that way on any known confirmed Barks painting.
The same way goes for the brush strokes.
Another give away that it's not Barks is that the person who painted this didn't know how to connect the leg with the feathers at the upper part of the leg.
Take a look at the painting you got and compare to other images of confirmed Barks paintings. See how the feathers are painted just wrong on the painting you have?
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For those of you on the Collectors Society Forum who does not know me:
I have studied the work of Barks for many, many years. I'm also working at Egmont Publishing in Sweden and we published a book featuring the oil paintings by Barks back in 2011: "Carl Barks Målningar och teckningar".
A 400+ pages thick book covering much that was not in the american book. A great reference source when you want to study his paintings.
I also work as a -script writer and artist for comics. As a professional in this business there's not one artist that I have studied more than Barks.
Now, we'll see what happens. At least I have said what I think. :-)
/Joakim.