All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
The partnership you described has different forms of brokerage contracts which revolve around a single aspect, which is that your partner who is the general manager of marketing in a factory introduced you to the factory in which he works to market for it certain commodities (goods/fabric) or to sell to it certain commodities (yarn) as well. Hence, we have to consider that partner in two ways: Firstly, he is an employee at his factory and a responsible agent for marketing its commodities. Secondly, he also sells to that factory because he is a partner in the brokerage company.
Accordingly, we say that if that company has full knowledge of the details of that matter and allowed the buying and selling of that person through his company, then the matter is permissible and there is no harm in that, according to the most preponderant opinion. However, if that company does not know about the details of that matter, then it is not permissible for that person to be an agent for that company and at the time he buys from it for himself or sells to it from himself.
Remember that brokerage is based on mediation between the seller and the buyer to bring about a sale. So, there is nothing wrong with taking commission for that from the seller and buyer or from one of them if this is done according to a certain tradition or condition. For more benefit, please refer to Fatwa 82302.
As for what you have mentioned that brokers distribute commission among them on different percentages on which they agree, then there is nothing wrong with that as long as there is mutual consent among them.
With regard to making the fees of the broker a percentage not a certain sum of money, then scholars hold different opinions regarding it. Anyway, there is no harm in adopting the opinion of those who allowed it to remove difficulty.
For more benefit, please refer to Fatwa 119330.
Allaah Knows best.