What blood type is a person if their clump in anti or b?

If a person's blood clumps in both anti-A and anti-B serum, it means that their red blood cells have both A and B antigens on their surface. This blood type is known as AB positive or AB negative, depending on the presence or absence of the Rh factor. People with AB blood type are universal recipients, which means they can receive blood transfusions from any blood group without experiencing an immune reaction.