This Arkansas case is really unusual. A woman discarded a lottery ticket into the trash when she mistakenly thought it was not a winner. Another woman fished it out of the trash and collected a million dollars. Now it is in court and the women who threw it away was deemed to be the rightful owner. Details of the story are at http://www.ajc.com/news/nation-world/2-arkansas-women-fight-1430405.html
Normally when property is abandoned, you lose your right of ownership. This is why law enforcement is allowed to search your trash without a warrant, because you are deemed to have abandoned it. There must be some wrinkle in the Arkansas lottery law which supersedes the general rule.