Calfrac Well Services Ltd. investor Wilks Brothers LLC on Oct. 5 raised its hostile bid for the oilfield services company to as much as 25 Canadian cents per share from a prior 18 Canadian cents.

Calfrac last month rejected the prior offer and said it was sweetening its recapitalization plan to reduce debt, at a time when its market value has shrunk to about C$22.5 million since the crash in fuel demand caused by the COVID-19 pandemic.

Calfrac declined to comment on the sweetened offer.

Its shares rose 3 cents to 18.5 cents in morning trading.

Wilks Brothers, led by oil billionaires Dan and Farris Wilks, has been acquiring stakes in hard-hit services firms in the United States and has been trying to buy Calfrac's U.S. business since July. The company owns nearly 20% of Calfrac.

The investor group on Oct. 5 said its new offer would go up to 25 Canadian cents per share, provided the total deal amount does not exceed $21.1 million.

Under the Calfrac management offer, shareholders can choose to either take 15 Canadian cents in cash for each share held and two warrants or can hold on to their shares and take just the warrants.

A special meeting of Calfrac shareholders to vote on either offer is scheduled for October 16.