May 20 (Reuters) - Palo Alto Networks ( PANW ) forecast

fourth-quarter billings above Wall Street estimates on Monday, a

sign that clients are turning to the cybersecurity firm for its

integrated software security tools.

The company expects fourth-quarter billings to be between

$3.43 billion and $3.48 billion, compared with analysts' average

estimate of $3.45 billion, according to LSEG data.