A pumpjack works at a well head on an oil and gas installation near Cremona, Alta., Saturday, Oct. 29, 2016. Calfrac Well Services Ltd. says a Texas company's proposed restructuring plan doesn't have sufficient support from unsecured noteholders so Calfrac will continue with a debt-for-stock swap announced in July. THE CANADIAN PRESS/Jeff McIntosh

Texas-based suitor Wilks Brothers, LLC, is sweetening its hostile takeover offer for Calgary-based Calfrac Well Services Ltd. by raising its bid to 25 cents per share from 18 cents.

The bid carries a maximum cash payout of $21.1 million, which Wilks says would cover all of the shareholders other than Matco Investments Ltd. (controlled by Calfrac chairman Ron Mathison) and officers and directors of Calfrac, as well as Wilks' stake of just under 20 per cent.

It says those shareholders have said they won't sell to Wilks anyway, so the cash will go to those who will. It says it will guarantee in any case that each shareholder would be able to get at least 18 cents in cash.

Wilks opposes management proposals for a court-supervised reorganization under the Canada Business Corporations Act, the latest of which would allow each shareholder to elect to be paid 15 cents per share in cash, from a maximum pool of $10 million.

The company has also offered to issue two warrants per share allowing the holder to buy more shares at an exercise price of five cents each for three years.

Calfrac says its senior unsecured noteholders, who hold US$431.8 million in debt plus interest, continue to support the amended plan which would allow it to carry on as an independent company. Its reorganization must be supported by two-thirds of debtholders and shareholders in separate votes to be held Oct. 16.