Prospective explorers generated US$159 million in high bids for 151 tracts covering 835,006 acres in federal waters. A total of 27 companies participated in the auction.

BHP was the second most successful bidder in the auction, spending more than US$41 million (A$60.6 million) and taking 20 blocks, increasing its footprint as the only larger Aussie company in the region.

The Australian mining and petroleum giant offered the most cash for a single  block in the entire auction, bidding US$22.5 million (A$33.3 million) for a block in the Green Canyon area, near some of Aussie junior Otto Energy's assets.

In total BHP's tract size, or acreage won in the lease sale, stretches over 115,200 sq.km in the US Outer Continental Shelf region.

Other majors Chevron Corporation picked up 18 blocks, Equinor and BP each won 23 blocks, while Shell won 12 blocks.

Bidders are not guaranteed winners as the Bureau of Ocean Energy Management has 90 days to review the bids.

While the amount of high bids was 35% lower than the previous sale this year, combined the 2019 sale is the highest since 2015. 

"The Gulf of Mexico is the crown jewel of our nation's energy portfolio," BOEM director Mike Celata said.

"As one of the most productive basins in the world, the development of its resources are (sic) essential to the nation's energy security."

Operators will pay a 12.5% royalty on leases in water depths less than 200 metres while projects in deeper waters will be subject to an 18.75% royalty rate.

Revenues received from Outer Continental Shelf will go directly to the US Treasury, Gulf Coast states (Texas, Louisiana, Mississippi, and Alabama), the Land and Water Conservation Fund, and the Historic Preservation Fund.

The National Ocean Industries Association described the result of the auction as "modest" but reflected the "cautiously optimistic attitude" of an offshore industry still in recovery.

"While companies have improved the efficiency of their operations and rig rates and supply chain prices are more competitive, oil prices remain flat," NOIA vice president of communications Nicolette Nye said.

"Bidding activity… may reflect the slower than desired improvement in prices. There is also uncertainty surrounding pending regulatory actions such as financial assurance and fair market valuation."