Amazingly, there are still people ‘out there’ who think that anything on the web is free for them to use (or share) on the internet, but that is simply not true.
In general, most images and photos are protected under copyright, meaning that anyone wanting to use them e.g. for a company website, their own website, blog, news release etc., will need to seek permission from the copyright owner(s).
The copyright owner (creator) means the person who creates the image (e.g. a photographer), unless that person created the work when employed by a company. In that case, the company will generally be the copyright holder.
You can only use stuff from the web without permission for reasons such as private study, or non-commercial research, or if the work specifically says it is copyright free and can be used as such.
I have had my photos stolen off the internet quite a few times, hence this post on how copyright law applies to photos and images.
Luckily, there are now easy ways to find out who is using one’s photos, although it can be a little time consuming if you’re not a company such as Getty Images (and other image libraries), who have access to image recognition software.
I am pleased to say that I have had almost 100% success in tracking down those who have stolen my work, and have succeeded in getting most of the images removed, or coming to some kind of acceptable usage agreement.
There is comprehensive information on copyright law regarding images here.