What is the legal ruling regarding a business partnership in which one partner contributes the entire capital and the other contributes his effort, then the financing partner requests the dissolution of the partnership after most of the capital has been spent on preparations and before the work has even begun?

The scenario described regarding the company is a mudarabah (definition) (partnership where one party provides the capital and the other provides labor). The fundamental principle in mudarabah is that the entrepreneur (worker) does not guarantee the capital. If he guarantees it, the contract becomes invalid. Therefore, if your signature on the check was as a guarantee or a loan, then the company (contract) is invalid. However, if the signature was merely a formality without intending a guarantee, then the mudarabah partnership is valid and permissible. Either party has the right to dissolve it, unless doing so would cause severe harm to the other party. The worker does not guarantee the capital unless his negligence, dereliction, breach of the capitalist's (investor's) terms, or misleading information is proven. In case of dispute, the matter is referred to the Sharia (definition) courts.