Hello, I have been running a web design business for about 6 years as a freelancer, then i found that I must expend further, rent an office, buy equipments and furniture and register the company for VAT and taxes.

Then I discussed this issue with a childhood friend, so he suggested to invest with me in this business. He payed all the expenses and played a role in doing the legal papers to start up the company.
N.B. he own an electronic shop, medium business (8 employees).

Both we agreed on the following:
He is not involved in day to day management.
He is a silent partner.
He will do the company setup only.
Some times, when we run out of projects he will make some contact with his customers to ensure a non stop running job.
I take care of everything, accounting, design, development, hosting and domain names, customer care, collecting payments, A to Z.

Now, 1 year and a half passed, He obtained double what he invested to the start up the company.

My question:

I think we must modify the agreement, because personally i think 50/50 is not fair for a silent partner doing nothing but ensuring projects continuity, right ?

During this year and a half, 20% of clients are his connections, the rest are from my part.

I'm thinking to modify the income percentage. what do you think is the fair % for both of us ?

I appreciate your advises