The Securities and Exchange Commission has signed off on SoftBank's paperwork regarding its proposal to buy a substantial portion of Sprint Nextel (NYSE:S), SoftBank announced yesterday.

This means Sprint can start mailing out its definitive proxy statement relating to the transaction to the company's shareholders.

A vote on whether Sprint should accept SoftBank's offer to buy 70% of the company will be held on June 12 at a special stockholders' meeting. The proxy statements Sprint will mail out will solicit shareholders' approval of the deal.

"The successful completion of the SEC review and the commencing of the mailing of the definitive proxy statement demonstrate the continued rapid progress we are making in closing our transaction with Sprint," SoftBank Holdings president Ron Fisher said.

SoftBank's announcement also stated it believed its $20.1 billion offer for part of Sprint would create more value for Sprint shareholders than would what it called the "highly leveraged" $25.5 billion proposal from DISH Network (NASDAQ:DISH).