This is the kind of bar of soap I am talking about. It's kind of a contoured oval.
I know there are copyrights on soap shapes. I've read several soap shape patents like Theodore G Brown's hollow bar of soap designed to contain slivers of old soap and Douglas Lee's helical soap.
I've tried to go through Conopco Inc's list of patents (the trademark holder for Dove) but I can't seem to find much. They also own a plethora of other companies though so it's been challenging to swift through.
On that note I also looked for subsidiaries of Unilever (they own Dove) to see if any of them make similarly shaped bars of soap but it doesn't seem like it. Brands of soap outside of Unilever such as Irish Spring (owned by Colgate-Palmolive) do sell contoured/"dog bone" soap but I don't recall seeing any that match Dove's design.
I did find a book called Chemical Product Design: Towards a Perspective through Case Studies from 2007 and chapter 9 is titled "Design of the Dove Beauty Bar" which sounded promising but it seems to be mostly about the chemical composition and reducing soap scum in bathtubs. This is also apparently one of the theories as to why they are branded as beauty bars instead of soap. The other theory being it was an advertising tactic by David Ogilvy to appeal to women.
Someone on Reddit claims their grandfather invented the shape of Dove soap and posted the original wooden models. They backed up their claims by getting into contact with Unilever. I couldn't find any useful information in the comments.
I could probably go to a grocery store and see if any other brands have similarly shaped soap and cross reference that with the release of that style of soap by Dove to see if the copyright has lapsed but that would probably mean looking for old advertisements.
For context I was in the shower thinking about different shapes of soap and it made me wonder if that specific design (contoured oval) was originally chosen primarily to either:
A) Minimize the amount of contact on surfaces after being used to limit residue build up and prevent it from becoming stuck to tubs, shower, sinks, and so on.
B) Work better with the human body by maximizing the area that comes into contact with skin and wearing more evenly.
I imagine these days Dove would say both but that feels a bit like saying the stay-on-tabs you find on canned drinks were designed with a hole to hold your straw in place or keep bees out of your drinks during the summer.
All of this made me wondering if there was a patent somewhere and I've now spent about two hours looking for it. I don't really know why I became so invested in this. I suspect there's going to be a simple answer.
It's a little bit more than that. There are 8 categories:
Sculpture is a type of visual work that can be copyrighted. So are architectural works. Not that a bar of soap would likely qualify as a sculpture, but there are 3 dimensional shapes that can be copyrighted.
If it's not already in common use when trademarked, even simple shapes can be trademarked. Simple colors can be trademarked as well: UPS trademarked its shade of brown, Tiffany has trademarked its shade of blue. Specific design elements can be trademarked as well, like the recognizable Burberry check pattern, the iconic glass bottle shape of Coca Cola, etc.
And the Dove soap bar shape isn't just a generic oval. It's a precise 3 dimensional shape, with a raised center and a gradual taper to the vertical edges all around.
I couldn't find a registered trademark, but the shape is distinctive enough that they probably would be able to trademark it if they wanted to (or even enforce an unregistered trademark in that shape, at least in the U.S.).