June 20 (Reuters) - U.S. corporate travel and expense

company Navan on Friday disclosed it had confidentially filed

for a U.S. initial public offering, as investor optimism for new

listings grow.

The terms of the offering were not disclosed.

Activity in the U.S. IPO market, which started the year on a

slower footing, has shown signs of a sustained revival after a

couple of fresh flotations received overwhelming investor

support.

Navan, founded in 2015 as TripActions, began as a corporate

travel management platform aiming to streamline services offered

by traditional players such as American Express ( AXP ) and SAP

Concur.