Peace be upon you. According to Grand Ayatollah Sistani (may Allah preserve him), these contracts are not valid in many cases of their trading, but one does not incur sin by engaging in them unless they involve usury. Grand Ayatollah Khamenei (may Allah preserve him) states that committing to a contract for a specified time is permissible, and transferring it to another party is also allowed. However, using leverage as a loan with interest is usury and forbidden. In contrast, if it is for fees for services rendered and within the customary limits, there is no issue. Additionally, receiving what is given within another legitimate contract, such as a partnership, is also permissible. May you be successful in all good.