Do I need liability release forms for others riding my horse?

I'm boarding my horse at the barn I take lessons at. My schedule has gotten busier so my instructor has other riders take lessons on my horse. Im moving to a house with a barn, riding ring, and paddocks all set up for him. I plan on taking him home within the next few months. No one will ride him except me and my family once he is home. But until then, do I need some release form for these people riding my horse? If so where can I get one? Thanks