A group of news organizations, camera makers, and technology companies have joined together to create a web tool called Verify for checking the authenticity of images for free. If the image has a digital signature, the site will display the date, location, and other credentials for the image. The authentication technology is now adopted by Nikon, Sony, and Canon.
https://www.pcmag.com/news/camera-companies-are-working-on-technology-to-watermark-real-images