EXCLUSIVE-Elliott's Evergreen submits offer for Gigamon -sources

Sept 11 (Reuters) - Elliott Management Corp's private equity arm has submitted a bid to acquire U.S. networking software maker Gigamon Inc, according to people familiar with the matter.

Reuters could not confirm Elliott's offer price for Gigamon, which had a market capitalization of about $1.58 billion based on its closing price on Friday. Evergreen has secured financing from two investment banks and made a formal bid in recent days, the sources added, asking not to be named because the matter is private.

Elliott and Gigamon declined to comment. Gigamon's shares jumped 4.5 percent to $44.27 in afternoon trading on Monday. (Reporting by Liana B. Baker and Michael Flaherty in New York; Editing by Leslie Adler)