The collapsed Sanyo Securities Co. has decided to formally file for bankruptcy, after a year of failed attempts to revive itself under a court-mediated rehabilitation procedure, industry sources said Monday.

It plans to begin bankruptcy procedures as early as next month, the sources said. Last November, Sanyo became the first securities firm in recent history to file for court protection from creditors and has been seeking a buyer to revive the medium-size brokerage.

But Sanyo almost gave up that effort in June, when it started liquidation preparations. As of the end of October, Sanyo had nearly 20 billion yen in customer assets deposited in some 40,000 accounts. It is negotiating with Osaka-based NCS Securities over the possible sale of its assets and its membership in the Tokyo Stock Exchange, the sources said.