Actually not - as reported in the article, the legal terminology is just that, "seizure", as they had stolen property and thus subject to that legal definition.
Receiving no formal request for the painting’s return, we felt we were repatriating of our own volition. Reading the necessary paperwork, however, there was no avoiding the terminology being used: seizure.
Thank you. I am not a lawyer, but I did spend the night at a Holiday Inn;)