Oilfield services provider Oil States International said it sold its casing and tubing business to a private company for $600 million, a day after activist investor Jana Partners disclosed a higher stake in the company.

Oil States expects to use the proceeds to fund its increased share repurchase programme and to repay debt. The company raised its share buyback programme to $500 million from $200 million.

Oil States said the sale would help it invest in its accommodations, well-site services and offshore products businesses.

The company said in May it was considering spinning off its accommodations business, which provides housing for energy industry workers in remote locations in Canada, the US and Australia. Oil States sold the business to Marubeni-Itochu Tubulars America, a unit of Japan’s Marubeni-Itochu Steel. Marubeni-Itochu Steel is jointly owned by trading houses Marubeni and Itochu.

Jana Partners, headed by Barry Rosenstein, raised its stake in Oil States to 11.7 per cent from 9.1 per cent, according to a regulatory filing. Oil States’ tubular business, Sooner, distributes casing and tubing used in drilling and completion of oil and natural gas wells primarily in North America.

Pricing for tubular services fell in 2012 and has remained depressed this year due to higher imports and rising domestic capacity.