It is common practice that photos that are found somewhere on the internet are published on a website without crediting the source. Many private individuals and businesses are unaware that this is not allowed or they underestimate the consequences. That can be a very expensive mistake. The search engines nowadays used by rightholders have become so effective that basically every photo can be traced. Even if such a photo is removed from the website at the rightholder’s first request, the website owner is liable for compensation to the amount of hundreds of euros. If he refuses to pay, he runs the risk of a decision by the subdistrict court, in which the judgment on damages might be slightly lower but it will include an order to pay the full costs of the proceedings of up to several thousands of euros. Subdistrict court judgments to this effect are increasing. And there are many more amicable settlements, some with confidentiality clauses, that remain below the radar. The enforcement of copyright regarding photos on the internet has become a profitable business model for some photographers and their lawyers.
Using a photo on a website without the permission of the rightholder is not allowed, especially not without referring to the source. If the source is mentioned and the author is correctly named, the use of the photo might be qualified as a legally permissible citation, but only if its use is functional and subordinate. Usually, however, source and attribution are lacking, in which case there can be no question of a permissible citation. A subdistrict court judge therefore has no other option than to rule that it constitutes copyright infringement. Even if the photo has been removed from the website at the first request. Subsequently, damages to the amount of several hundreds of euros will be awarded, in some cases at a rate of 25 to 200% above the base rate due to the absence of a proper reference to source or name, to cropping the photo or to loss of exclusivity.
In copyright cases it is mainly the order to pay the full costs of the proceedings that results in people, often without legal representation and claiming unmeritorious defences, having to pay a lot of money. Lawyers who do have the proper knowledge of copyright laws reluctantly have to advise their clients settle claims for hundreds of euros and to advise their clients to be more careful in the future.
So my advice to you is do not re-use a photo taken from the internet on the internet, because it might cost you hundreds of euros.