Corvis Corp. disclosed yesterday that it owns most of St. Louis-based C III Communications LLC, a firm that agreed to acquire the fiber-optic network of Broadwing Inc.

The deal was announced last month, but the size of Corvis's investment in the venture wasn't disclosed until yesterday, when the Columbia fiber-optics equipment company filed its annual report with the Securities and Exchange Commission.

Corvis owns 96 percent of C III, which it incorporated specifically to complete the Broadwing deal.

Corvis pledged $128 million of the $129.3 million price for the Broadwing assets, as well as $50 million to fund its 2003 operations.

Though Corvis owns almost all of it, the venture was set up as a separate entity so that other investors could be brought in. Corvis spokesman Andrew Backman said the company is looking for additional investors in C III, which means its total cash commitment to C III, as well as its percentage ownership of it, could decline.

Cincinnati-based Broadwing was an investor in Corvis and was one of its six customers. Broadwing was the first to install Corvis's products on its fiber-optic network, which spans 18,700 miles.

Broadwing, which with this deal exits the fiber-optic network business, will retain 3 percent ownership of C III. The other investor in C III is Cequel III LLC, an investment company based in St. Louis.

Corvis has traded below $1 since last May and closed yesterday at 60 cents, up 5 cents. Though its business declined rapidly in 2002 and it lost $507.8 million last year, it ended the year with $504.4 million in cash and investments.