When you contribute with imagery to Mapillary you submit them under Mapillary’s terms. All images on Mapillary are shared under a CC-BY-SA license, which in short means that anyone can look at and distribute your images, and even modify them a bit, as long as they give attribution. This is an example of a perfect attribution when you use Mapillary imagery on your website, blog etc:
“Title" <Link to Mapillary image> by “username” <Link to user profile>, licensed under CC-BY-SA.
When you upload imagery to Mapillary you give Mapillary the rights to use the images for commercial purposes. However, you still own the full rights to the images you contributed, and you always will.
Feel free to contact us at firstname.lastname@example.org if you’re unsure about licenses and attribution and we’ll be happy to guide you.