Notwithstanding any other provision of this Article IV , the Celgene Parties acknowledge and agree that the Shares may be disposed of only pursuant to an effective registration statement under, and in compliance with the requirements of, the Securities Act, or pursuant to an available exemption from, or in a transaction not subject to, the registration requirements of the Securities Act, and in compliance with any applicable state and federal securities laws. In connection with any transfer of Shares other than (i) pursuant to an effective registration statement, (ii) to the Company or (iii) pursuant to Rule 144, the Company may require the transferor thereof to provide to the Company an opinion of counsel selected by the transferor and reasonably acceptable to the Company, the form and substance of which opinion shall be reasonably satisfactory to the Company, to the effect that such transfer does not require registration of such transferred Shares under the Securities Act. As a condition of transfer, any such transferee shall agree in writing to be bound by the terms of this Agreement and the Registration Rights Agreement and shall have the rights of the Celgene Parties under this Agreement and the Registration Rights Agreement with respect to such transferred Shares.