** Shares of construction firm Fluor FLR.N up 8.3% at $51.85 in premarket trading
** Activist investor Starboard Value has taken a nearly 5% stake in the firm, two sources familiar with the matter told Reuters on Monday after WSJ's report, which first reported the news
** Starboard and Fluor did not immediately respond when contacted by Reuters
** Fluor has a nearly 40% stake in nuclear reactor developer NuScale Power SMR.N, which has gained this year, driven by surging demand for data centers and AI technologies
** Starboard believes that Fluor's core business is being undervalued in the market relative to the value that investors are attributing to the NuScale stake, sources said
** Starboard founder Jeff Smith is expected to talk about some of the firm's investment ideas at the 13D Monitor Active Passive Investment Summit in New York on Tuesday
** Average rating of 9 brokerages equivalent to 'buy', median PT is $50.5 - data compiled by LSEG
** As of last close, stock down 2.9% YTD
(Reporting by Kanchana Chakravarty in Bengaluru)
((Kanchana.Chakravarty@thomsonreuters.com;))