"In corporate finance, Contingent Value Rights (CVR) are rights granted by an acquirer to a company’s shareholders, facilitating the transaction where some uncertainty is inherent. CVRs may be separately tradeable securities; they are occasionally acquired by specialized hedge funds."
In simple terms it is a way to take over a company without losing a big product’s potential it is favorable for smaller companies which have a great product but lack the money to sell it. or even develop it! Basically, the smaller company retains an interest similar to a royalty on this should it prove to be successful....normally, the investment bankers will handle this or even the company wishing to acquire the smaller company (AVXL)....hope that is fairly clear.