Firstly it is worth noting that whilst most kite insurance policies cover you for items accidentally dropped from a kite, most do not cover those dropped deliberately. In June 2010 a number of clubs have had a clause added to their insurance to caver parachuting soft toys.
Under The Air Navigation Order 2005 you are required to have an exemption before dropping an article by parachute. These exemptions can be applied for from The Civil Aviation Authority. A sample can be found here. A few clubs already hold these exemptions and the required document "BMISS Aerial Applications Manual" is currently being saught.
