Swiss drug developer Roche is boosting its hostile tender offer for biotechnology pioneer Genentech by 7.5 percent to $93 per share.
Roche's $86.50-per-share offer was set to expire March 12, but the company said it had only tendered 500,000 shares as of March 5. Genentech Inc. has about 1.05 billion shares of stock outstanding.
The updated offer is extended to March 20.
Roche had initially offered South San Francisco-based Genentech $89 per share in July, but that bid was rejected by the board of directors. Analysts say the previous $86.50 bid was too low. Genentech has speculated that it could fetch up to $112 per share.
Shares of Genentech surged $8.34, or 10.2 percent, to $89.98 in afternoon trading Friday.