This statement seems to arise from a fundamental misconception about copyright law, particularly among the internet’s younger users, that copyright is simply a claim of title. By writing “No copyright intended!”, the user seems to be saying: “I’m not claiming that this is mine!”
Unfortunately for those users, however, copyright law does not care about intention. Copyright infringement is sometimes called a “strict liability” action, which means that if you exercise one of the copyright owner’s exclusive rights without permission or legal exception then you have infringed copyright – there are no if, buts or maybes about it. The copyright owner doesn’t have to prove that you meant to infringe their work, or even that you knew what you were doing when you infringed. Intention is irrelevant to copyright infringement.
What’s the best thing to do about this? Be aware of your rights and the rights of other creators. That’s what I’m aiming to help you with via this blog. Any questions? – Feel free to contact me.