The Prophet ﷺ said, "If a man gets up from his seat and then returns to it, he has the greater right to it. And if he has a need, gets up to attend to it, and then returns, he has the greater right to it."
عن النبي ﷺ قال: إذا قام الرجل من مجلسه فرجع إليه فهو أحق به، وإن كانت له حاجة، فقام إليها ثم رجع فهو أحق به.
Reported by Tirmidhi (2751), Ahmad (15484), and Tahawi in Sharh Mushkil (1277), all through the route of Khalid bin Abdullah Wasiti, from Amr bin Yahya, from Muhammad bin Yahya bin Habban, from his uncle Wasi bin Habban, from Wahb bin Huzaifa, who related it. Its isnad is sahih. Tirmidhi said, "This is a hasan sahih gharib hadith."His statement, "when the man gets up," means with the intention of returning to that spot at that time, and this is known by certain indicators, such as leaving something in that place, or telling the person sitting next to him.