THE CORPORATE LIBRARY

Related Party Transactions and Outside Related Director Information

USG Corporation (USG)

3/31/2006 Proxy Information

The Corporation has entered into several agreements with related parties as described below. Copies of the agreements were filed as exhibits to a Form 8-K filed with the SEC on January 30, 2006, which is available at the CorporationÕs website, www.usg.com, in the InvestorsÕ information area.

Equity Commitment Agreement

As mentioned above under the section titled ÒCorporate GovernanceÓ, the Corporation entered into an equity commitment agreement with Berkshire Hathaway Inc., whereby Berkshire Hathaway, the CorporationÕs largest stockholder, committed to purchase from the Corporation, at $40.00 per share, all of the shares of Common Stock offered pursuant to the rights offering that are not issued pursuant to the exercise of rights in the rights offering, up to a total commitment of $1.8 billion. The Corporation paid the backstop purchaser a one-time, non-refundable fee of $67 million for this commitment. The Corporation also agreed to pay certain of Berkshire HathawayÕs costs and expenses relating to its entry into the backstop commitment and related agreements.

At a hearing on February 23, 2006, regarding the Berkshire Hathaway backstop commitment, the Bankruptcy Court, after considering alternative proposals, entered an order approving the Berkshire Hathaway backstop commitment. Under the terms of the equity commitment agreement, Berkshire Hathaway deposited $1.8 billion in treasury securities into an escrow account to secure performance of its obligations under the agreement and the Corporation paid Berkshire Hathaway its $67 million fee.

Amounts remaining in the escrow account after performance by Berkshire Hathaway of its obligations under the backstop commitment will be returned to Berkshire Hathaway.

Berkshire HathawayÕs commitment to purchase shares of Common Stock that are not otherwise issued pursuant to the exercise of rights in the rights offering expires on September 30, 2006, subject to extension to November 14, 2006, in specified circumstances, including the payment of an additional non-refundable $6.7 million fee.

ShareholderÕs Agreement

In connection with the equity commitment agreement, the Corporation and Berkshire Hathaway entered into a shareholderÕs agreement whereby Berkshire Hathaway agreed, among other things, that for a period of seven years following completion of the rights offering, except in limited circumstances, it will not acquire additional beneficial ownership of USG voting securities if, after giving effect to the acquisition, Berkshire Hathaway would own more than 40% of USG voting securities on a fully diluted basis (or such higher percentage of voting securities that Berkshire Hathaway will own after making any purchases required under the equity commitment agreement described above). Berkshire Hathaway further agreed that, during that seven-year period, it would not solicit proxies with respect to USG CorporationÕs securities or submit a proposal or offer involving a merger, acquisition or other extraordinary transaction unless the proposal or offer is (1) requested by the USG board of directors or (2) made to USGÕs board of directors confidentially, and is conditioned on approval by a majority of the voting securities of USG not owned by Berkshire Hathaway and a determination by the board of directors as to its fairness to stockholders and, if the proposed transaction is not a tender offer for all shares of USG common stock or an offer for the entire company, is accompanied by an undertaking to offer to acquire all shares of USGÕs common stock outstanding after completion of the transaction at the same price per share as was paid in the transaction. The shareholderÕs agreement also provides that, with certain exceptions, any new shares of Common Stock acquired by Berkshire Hathaway in excess of those owned on the date of the agreement (and shares distributed on those shares, notably in the rights offering) will be voted proportionally with all voting shares. Berkshire Hathaway also agreed that if purchases or sales of USGÕs common stock by it or specified affiliates would prevent the Corporation from carrying back a net operating loss attributable to a specified payment to the Section 524(g) trust, Berkshire Hathaway will not, upon notice from the Corporation, make such purchases or sales until the Corporation has made its first payment under the contingent payment note issued to the Section 524(g) trust or notifies Berkshire Hathaway that this limitation is no longer needed.

Under the shareholderÕs agreement, for the same seven-year period, the Corporation agreed to exempt Berkshire Hathaway from the CorporationÕs existing or future poison pills to the extent that Berkshire Hathaway complies with the terms and conditions of the shareholderÕs agreement. If there is a shareholder vote on a poison pill that does not contain this agreed exemption, Berkshire Hathaway may vote without restriction all the shares it holds to approve or disapprove the proposed poison pill. The Corporation and Berkshire Hathaway also agreed that, after the seven-year standstill period ends, during the time that Berkshire Hathaway owns USG equity securities, Berkshire Hathaway will be exempted from the CorporationÕs poison pills, except that the CorporationÕs poison pills may require that Berkshire Hathaway does not acquire (although it may continue to hold) beneficial ownership of more than 50% of USG voting securities, on a fully diluted basis, other than pursuant to an offer to acquire all shares of USG common stock that is open for at least sixty calendar days.

Escrow Agreement

In connection with the equity commitment agreement, the Corporation and Berkshire Hathaway entered into an escrow agreement relating to the deposit by Berkshire Hathaway on March 7, 2006, of $1.8 billion in treasury securities to secure performance of its obligations under the equity commitment agreement. Pursuant to the escrow agreement, amounts remaining in the escrow account after performance by Berkshire Hathaway of its obligations under the backstop commitment will be returned to Berkshire Hathaway. The escrow agreement will terminate upon the disbursement of all escrowed funds in accordance with the terms of the agreement.

Registration Rights Agreement

In connection with the equity commitment agreement, the Corporation and Berkshire Hathaway entered into a registration rights agreement whereby Berkshire Hathaway received demand and piggyback registration rights with respect to its shares of USG common stock. The registration rights agreement entitles Berkshire Hathaway and specified affiliates to make three demands for registration of all or part of the holderÕs or holdersÕ common stock, subject to certain conditions and exceptions. The registration rights agreement also provides that, subject to certain conditions and exceptions, if the Corporation proposes to file a registration statement under the Securities Act with respect to an offering of equity securities on a form that would permit registration of shares of USG common stock that are held by Berkshire Hathaway or specified affiliates, then the Corporation will offer Berkshire Hathaway and its affiliates the opportunity to register all or part of their shares on the terms and conditions set forth in the registration rights agreement.

4/1/2005 Proxy Information

On June 25, 2001, the Corporation and 10 of its U.S. subsidiaries filed for reorganization under chapter 11 of the U.S. Bankruptcy Code. As a result, all of the executive officers have been associated with a corporation that filed a petition under the general bankruptcy laws within the last five years..

4/1/2004 Proxy Information

On June 25, 2001, the Corporation and 10 of its U.S. subsidiaries filed for reorganization under chapter 11 of the U.S. Bankruptcy Code. As a result, all of the executive officers have been associated with a corporation that filed a petition under the general bankruptcy laws within the last five years.

4/4/2003 Proxy Information

No related party transactions or special relationships reported for this company. Director relationships marked "Outside Related" at this firm will most often be former executives of the company. Additional information regarding these relationships will be added during our regular updates.