Is it permissible for the first partner to take possession of the share of the third partner who withdrew from the company, and only return his capital to him?

It is permissible for a partnership to be formed with capital from one party and capital and labor from another. Each capital provider becomes a partner in the company's capital proportionate to their contribution. As for the profit distribution, it is determined by agreement. If one of the partners wishes to withdraw, the company is valued to determine their share through what is called "estimated liquidation," where the company's assets are valued at market price to ascertain the profit. The withdrawing partner may sell their share to one of the partners, and the other two partners have the right of pre-emption to purchase in proportion to their shares. If one partner's share in the capital increases due to purchase, this does not necessarily mean an increase in their profit share unless there is a new agreement, especially if the work responsibilities change.