I am told that we can use copyrighted images in our lectures to students now as they are for purely educational purposes, as long as we correctly attribute them. That is to say there is no need to ask the permission of the copyright holders.
What is the status of using copyrighted images in conference talks? Does it also count as education?
As pointed out, this will depend on the country in which the talk is given. Let me restrict the question to the US and UK in that case. If anyone knows the situation in another country then it would be great to hear that too of course.
In the UK, the reason why I suggested you could use copyrighted material in lectures without asking permission was http://lti.lse.ac.uk/copyright/copyright-2014.php#education .