Saudi Aramco’s planned 5% float has spurred other Gulf NOCs to think likewise, both to raise cash and as a path to modernization and forging global partnerships.

Renowned for prizing their state energy assets, Gulf governments have long shown reluctance to go down the privatization route.

Before oil prices crashed in mid-2014, the region’s state energy firms largely financed themselves with government money.

But the sustained slump in oil prices over the last three years has...