10. Lease of contract

In a 20-year lease contract over a building, the lessee is expressly granted a right of first refusal should the lessor decide to sell both the land and building. However, the lessor sold the property to a third person who knew about the lease and in fact agreed to respect it. Consequently, the lessee brings an action against both the lessor-seller and the buyer (a) to rescind the sale and (b) to compel specific performance of his right of first refusal in the sense that the lessor should be ordered to execute a deed of absolute sale in favor of the lessee at the same price. The defendants contend that the plaintiff can neither seek rescission of the sale nor compel specific performance of a "mere" right of first refusal. Decide the case. [5%]