Shares rose 1.98% to $742.21 on Friday, topping the previous $728.85 peak set on 30 April and marking a second straight daily gain.
The move came in a mixed US market session, with the S&P 500 up 0.29% while the Dow Jones Industrial Average fell 0.31%.
Trading volume reached 1.3 million shares, above the 50-day average of 1.1 million; among peers, MasTec gained 5.93%, EMCOR rose 1.33%, and AECOM was flat.
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