It might be illegal for you to take a picture of the Eiffel tower at night. Copyright law gives the original creator of an object the rights to its sale and distribution as long as they live, plus 70 years. The Eiffel Tower’s copyright expired in 1993, legally allowing people to take, sell and publish photos of it during the day. However, the Eiffel Tower’s nighttime light show was added in 1985 and is therefore still protected under copyright. This means that technically it is illegal to share, sell, or publish photos and videos of the Eiffel Tower at night. However, the Eiffel Tower's copyright has never been enforced in court as it would have to be enforced on millions of tourists. But if you want to share photographs of the Eiffel Tower at night for commercial reasons, you may want to request permission.