Abu Dhabi's Aabar Investments, which scrapped a $1.7bn deal to take a majority stake in Arabtec two years ago, has raised its holding in the Dubai builder to 5.28 percent, according to a filing on the Dubai stock exchange on Monday.
The move makes the sovereign wealth fund one of the largest shareholders in Arabtec. The stake is held under Aabar Petroleum Investments, the filing showed.
Arabtec shares have risen 124 percent this year amid talk of an institutional investor buying up a stake. Neither firm had commented on the speculation.
The stock closed down 1.96 percent at 3.5 dirhams ($0.95) on Monday.
In 2010, the two firms said they would cooperate strategically after Aabar's bid to buy 70 percent of Arabtec was abruptly cancelled.