Halliburton, the second-largest U.S. oilfield services company, said its offer to exchange its shares for KBR stock was oversubscribed, with about 211 million shares tendered.
Because of the oversubscription, Halliburton said about 40% of the shares submitted will be accepted for exchange.
Halliburton for years has been working to split off KBR, the Pentagon's largest contractor in Iraq. The exchange offer will complete the separation of the two companies. KBR has faced several investigations into alleged overbilling in Iraq.
Shares of KBR , which began trading publicly in November, rose more than 1% on Tuesday amid a surge in trading volume.
Stockholders who own less than 100 shares of Halliburton common stock will not be subject to proration, the Houston-based company said.
Stockholders who delivered a notice of guarantee must deliver the tendered shares and required documents no later than 5 p.m. on April 5.
The company also said it expects to announce the final proration number after the expiration of the guaranteed delivery period and confirmation that offering conditions have been met or waived.