"We let Brigham be Brigham," Veronica Roa, Statoil’s vice president for early stage projects and land told a crowd at the Offshore Technology Conference in Houston on Wednesday.

The $4.4 billion acquisition, made in 2011, not only gave Statoil a core onshore position in the Bakken tight-oil play, it also rapidly grew the ranks of Statoil personnel with expertise in US unconventional plays and brought in a corporate culture that had proven successful in that sector, she said.

Statoil