Clayton Williams Increases Borrowing Base

Clayton Williams announced that, effective April 29, 2010, its bank group increased the borrowing base under the Company's secured revolving credit facility from $250 million to $300 million. The credit facility is provided by a syndicate of ten banks led by JPMorgan Chase Bank, N.A. All other material terms of the credit facility, including maturity, pricing terms and financial and non-financial covenants, remained unchanged.