I've found many images with logos of micro sites... I don't use Pinterest (and never did), have no idea what it is and how it works, but I don't think it's legal usage?

http://www.pinterest.com/pin/90001692527603228/     antique oil lamp from Depositphotos (large web size!)
http://www.pinterest.com/pin/196610339955214421/   yellow phone booth from Dreamstime
http://www.pinterest.com/pin/29906784998058747/

and more like that...

 

This way anyone can use anything anywhere...

I don't like it, but when the agency (like Dreamstime) puts the Pin button on their site, we don't have any way to use DMCA takedown to get the image removed. I've found one or two images on Pinterest in the past that were pinned from a blog post (which I assume was a licensed use) and Pinterest responded promptly to the DMCA notice.

If I thought that pinning images led to sales of licenses, I'd be fine with pinning watermarked images, but I don't think that's likely (given what I  understand the demographics and typical uses of Pinterest are). Perhaps because there's a buzz around social media for business or perhaps because they know more than I do, several of the agencies have their own boards on Pinterest:

http://www.pinterest.com/shutterstock/

http://www.pinterest.com/dollarphotoclub/

http://www.pinterest.com/dreamstime/

http://www.pinterest.com/123rf/

http://www.pinterest.com/fotolia/

http://www.pinterest.com/depositphotos/

http://www.pinterest.com/canstockphoto/

http://www.pinterest.com/veerideas/

http://www.pinterest.com/alamy/

http://www.pinterest.com/photodune/

And here is fresh answer from DP:
"It is a copyright violation. To post our images with our watermarks on is prohibited by our license agreement. Feel free to contact the person who posted your file on Pinterest. We will do our best to remove it from public access."

I think it's a copyright violation too, but when agencies are saying it's ok, it's gonna be pretty hard to fight it.

edit: I just clicked on the image in the first url of the original post, and it takes me to the general dp landing page, not a page for the actual photo. I clicked on the second one, and it actually takes me to the image on dt. So that's good. The third url image doesnt even have a watermark, that I could see. When I click on it, it links to sciencedaily.com, who likely paid for it because they have given credit to the contributor on Fotolia. But the pin means the contributor is getting ripped off. 

There are plenty of truly bad things to worry about in the stock business these days. Watermarked images on Pinterest is not one of them.

If you actually are concerned with this for some reason and feel inclined to spend any time doing anything about it, I might suggest setting up your own account and pinning your images from whatever agency pays you the best. So at least if your stuff does turn up in a search and someone clicks through to buy the image, you get decently compensated for it.

The "membership agreement" covers usage of the site and contents, even by non-members: http://depositphotos.com/member-agreement.html

There are plenty of truly bad things to worry about in the stock business these days. Watermarked images on Pinterest is not one of them.

If you actually are concerned with this for some reason and feel inclined to spend any time doing anything about it, I might suggest setting up your own account and pinning your images from whatever agency pays you the best. So at least if your stuff does turn up in a search and someone clicks through to buy the image, you get decently compensated for it.

And what about the non-watermarked images that get pinned over and over and over? Like the third image in the original post?

Consider it advertising.  Clicking on the link goes to the microstock site.

Not sure if you are talking to me, but the third image in the original post doesnt take me to any microstock site. There's a fairly large, unwatermarked image by a contributor at Fotolia, just ready and waiting to be pinned over and over and over again...for free. Advertising?

Which link are you clicking on to take you to a microstock site?