Wireless network component maker Finisar Corp. said yesterday it would buy Optium Corp., a Horsham supplier of telecommunication equipment, in an all-stock deal worth about $211.7 million.

Sunnyvale, Calif.-based Finisar makes equipment that allows high-speed connection over local-area networks. Customers include Hewlett-Packard and IBM.

Optium makes equipment for telecommunication networks and cable TV. Its customers include Alcatel-Lucent, Ericsson and suppliers to cable-TV companies, spokeswoman Veronica Rosa said.

Optium chief executive Eitan Gertel will become Finisar's CEO and will join its board, along with Optium board members Morgan Jones and Chris Crespi. Finisar's current CEO, Jerry Rawls, will remain as chairman.

Optium employs 400, more than half at its Horsham headquarters, Rosa said. She said the company had not announced whether headquarters would be in Horsham or in Sunnyvale.

Optium outsources much of its production, and Finisar is a manufacturer. The combined companies may move more of Finisar's production to cheaper overseas factories, but employment at Horsham could grow as the company designs more products, Rosa added, citing company statements in an investors' meeting after the deal was announced.

Gertel, a Drexel University graduate, started the company in 2001 with other veterans of JDS Uniphase. He ran that company's power-transmission division, also based in Montgomery County, from 1995 to 2001.

Optium stockholders will receive 6.262 Finisar shares for each Optium share they own.

At Thursday's closing price of $1.33 per Finisar share, the deal puts a $8.32 value on each Optium share. Optium had approximately 25.5 million shares outstanding as of March 11.

The acquisition price per share represents a 2.2 percent premium for Optium shareholders on yesterday's closing price of $8.14.

If the deal is approved as expected, Finisar shareholders will own approximately 65 percent of their company, and Optium shareholders will own approximately 35 percent.

The acquisition is subject to the approval of both companies' stockholders. Some directors, executives and affiliates have agreed to vote in favor of the deal. These agreements apply to approximately 7 percent of Finisar's and 34 percent of Optium's outstanding shares.

Finisar shares rose 20 cents yesterday to close at $1.53 in Nasdaq trading. Optium rose 89 cents to $9.03, also on Nasdaq.

Inquirer staff writer Joseph N. DiStefano contributed to this article.