(a) Open-end and closed-end companies For the purposes of this subchapter, management companies are divided into open-end and closed-end companies, defined as follows: (1) "Open-end company" means a management company which is offering for sale or has outstanding any redeemable security of which it is the issuer. (2) "Closed-end company" means any management company other than an open-end company. (b) Diversified and non-diversified companies Management companies are further divided into diversified