Consider whether the new partner actually acquired ownership of a capital interest,
or the validity of the transfer where the person who made the transfer retains substantial
control over the new partner's interest, such as:
Retention of management powers and control over assets essential to the business.
Limitation on the right of the new partner to withdraw or sell his interest;
Retention of control of the distribution of amounts of income;
Restrictions on the amounts of income to the donee partner.