** Credit bureau Equifax's EFX.N shares fall 4.1% to $249 premarket

** EFX lifts annual forecasts for full-year reported revenue by $35 million and adjusted EPS by $0.03 per share for foreign exchange

** Oppenheimer analyst Owen Lau says the outlook fell short of expectations

** "We believe it is a disappointment for the market, and could be a key question during the earnings call; specifically, whether the slowdown reflects underlying business challenges or simply stems from an abundance of conservatism," Lau says

** William Blair analyst Andrew Nicholas says the stock’s reaction will depend on whether investors see the lower second-half outlook as management being cautious or if July results suggest deeper issues

** As of last close, EFX stock up 1.9% YTD

(Reporting by Arasu Kannagi Basil in Bengaluru)

((ArasuKannagi.Basil@thomsonreuters.com;))