** Shares of cybersecurity co Palo Alto Networks PANW.O down about 4% at $175.75 in trading Thurs and on track for a third day of losses, with KeyBanc cutting its rating to "sector weight" from "overweight," citing concerns related to PANW's planned merger with CyberArk Software CYBR.O

** Among their concerns, KeyBanc analysts said in a note they don't see meaningful synergies and that they don't see a benefit "from either a replacement cycle, a first mover advantage into a new market, or as a natural extension to an existing product."

** In addition, the analysts said they had "increasing concerns recently following some customer and partner checks suggesting more aggressive behavior on pricing increases"

** The stock is down about 14% since Monday's close. On Tues, a news report said that PANW was in talks to acquire the Israeli firm. And on Wed, PANW announced the deal between the two companies

** D.A. Davidson and Mizuho cut their PTs on PANW

** The median 12-mo PT on the stock is at $215, based on LSEG data

** PANW is now down ~3% for the YTD compared with a roughly 10% gain in the Nasdaq .IXIC for that period

** U.S.-listed shares of CYBR were down 3.7% on Thurs

(Reporting by Caroline Valetkevitch)

((caroline.valetkevitch@tr.com))