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Whiting Petroleum Corporation (WLL) today announced that it has commenced an offer to exchange all of its outstanding, unregistered 6.25% Senior Notes due 2023 (the “Original Notes”) for new, registered 6.25% Senior Notes due 2023 (the “New Notes”).

The terms of the New Notes to be issued in the exchange offer are substantially identical to those of the Original Notes, except that the New Notes will not have securities law transfer restrictions, and the registration rights relating to the Original Notes and the New Notes will not provide for the payment of additional interest under circumstances relating to the timing of the exchange offer.

The exchange offer will expire at 5:00 p.m. New York City time, on July 1, 2015, unless extended by Whiting Petroleum Corporation. Valid tenders of the Original Notes must be made, and may be withdrawn at any time, before the exchange offer expires.

Documents describing the terms of the exchange offer, including the prospectus and transmittal materials for making tenders, may be obtained from the exchange agent, The Bank of New York Mellon Trust Company, N.A., by overnight delivery or mail at The Bank of New York Mellon Trust Company, N.A., Corporate Trust Operations, Reorganization Unit, 111 Sanders Creek Parkway, East Syracuse, NY 13057, or by facsimile (for eligible institutions only) at (504) 212-1610, Attention: Corporate Trust Operations Reorganizations Unit with confirmation by telephone at (315) 414-3349.

This press release does not constitute an offer to sell or the solicitation of an offer to buy securities. The exchange offer is being made only pursuant to a prospectus and the related letter of transmittal and only to such persons and in such jurisdictions as is permitted under applicable law.

About Whiting Petroleum Corporation

Whiting Petroleum Corporation, a Delaware corporation, is an independent oil and gas company that explores for, develops, acquires and produces crude oil, natural gas and natural gas liquids primarily in the Rocky Mountain and Permian Basin regions of the United States. The Company’s largest projects are in the Bakken and Three Forks plays in North Dakota, the Niobrara play in northeast Colorado and its Enhanced Oil Recovery field in Texas. The Company trades publicly under the symbol WLL on the New York Stock Exchange.