Baker Hughes did not offer any more details on the talks. Halliburton, for its part, said it “does not comment on potential merger and acquisition plans.” News of the deal was first reported in The Wall Street Journal. The newspaper did not mention a possible price for the acquisition.

If an agreement were to be reached, it would be one of the largest in the energy sector in recent years.

Baker Hughes (BHI), which has a market value of $26.1 billion, saw its share price surge 15% to $58.98 after the news broke Thursday.

Shares of Halliburton (HAL), which has a market value of $46.77 billion, were up about 1% to $53.79 at the close of regular trading.

Both companies help oil producers with their drilling operations.

Baker Hughes has 61,000 employees in more than 80 countries and is a leading supplier of oilfield services, products, technology and systems to the global oil and natural gas industry.

The news of the possible acquisition comes following a sharp decline in oil prices over the past few months, and at a time when oil drillers may be considering cutting back on production. On Thursday, oil prices fell below $75 a barrel for the first time in four years.

In September, Halliburton agreed to pay $1.1 billion to settle lawsuits related to the Gulf of Mexico oil spill in 2010, which claimed 11 lives.