Exhibit

The following is a brief description of the common stock, $0.01 par value per share (the “Common Stock”), of McKesson Corporation (the “Company”), which is the only security of the Company registered pursuant to Section 12 of the Securities Exchange Act of 1934 (the “Exchange Act”).

The following descriptions of our Common Stock and of certain provisions of Delaware law do not purport to be complete and are subject to and qualified in their entirety by reference to our amended and restated certificate of incorporation, our amended and restated by-laws and the Delaware General Corporation Law (“DGCL”). Copies of our amended and restated certificate of incorporation and our amended and restated by-laws have been filed with the Securities and Exchange Commission (the “SEC”) as exhibits 3.1 and 3.2, respectively, to our Form 10-K and Form 10-Qs. All of our outstanding shares of common stock are fully paid and non-assessable. Our common stock is listed on the New York Stock Exchange under the symbol “MCK.”

Dividend Rights. Subject to the dividend rights of the holders of any outstanding preferred stock, the holders of shares of Common Stock are entitled to receive ratably dividends out of assets legally available therefor at such times and in such amounts as our board of directors may from time to time determine.

Rights Upon Liquidation. Upon liquidation, dissolution or winding up of our affairs, the holders of Common Stock are entitled to share ratably in our assets that are legally available for distribution, after payment of all debts, other liabilities and any liquidation preferences of outstanding preferred stock.

The rights of holders of Common Stock may be materially limited or qualified by the rights of holders of preferred stock that we may issue in the future. Set forth below is a description of the Company’s authority to issue preferred stock and the possible terms of that stock.

Our amended and restated certificate of incorporation authorizes our board of directors, without further stockholder action, to provide for the issuance of up to 100,000,000 shares of preferred stock, in one or more series, and to fix the designations, terms, and relative rights and preferences, including the dividend rate, voting rights, conversion rights, redemption and sinking fund provisions and liquidation preferences of each of these series. Of the preferred stock, 10,000,000 shares have been designated Series A Junior Participating Preferred Stock. We may amend from time to time our amended and restated certificate of incorporation to increase the number of authorized shares of preferred stock. Any such amendment would require the approval of the holders of a majority of our shares of Common Stock entitled to vote.

Dividend Rights. The preferred stock will be preferred over the Common Stock as to payment of dividends. Before any dividends or distributions (other than dividends or distributions payable in Common Stock or other stock ranking junior to that series of preferred stock as to dividends and upon liquidation) on the Common Stock or other stock ranking junior to that series of preferred stock as to dividends and upon liquidation shall be declared and set apart for payment or paid, the holders of shares of each series of preferred stock (unless otherwise set forth in the applicable prospectus supplement) will be entitled to receive dividends when, as and if declared by our board of directors or, if dividends are cumulative, full cumulative dividends for the current and all prior dividend periods. We will pay those dividends either in cash, shares of preferred stock, or otherwise. With respect to each series of preferred stock that has cumulative dividends, the dividends on each share of the series will be cumulative from the date of issue of the share unless some other date is set forth in the prospectus supplement relating to the series. Accruals of dividends will not bear interest.

Rights Upon Liquidation. The preferred stock of each series will be preferred over the Common Stock and other stock ranking junior to that series of preferred stock as to assets, so that the holders of that series of preferred stock (unless otherwise set forth in the applicable prospectus supplement) will be entitled to be paid, upon our voluntary or involuntary liquidation, dissolution or winding up, and before any distribution is made to the holders of Common Stock and other stock ranking junior to that series of preferred stock, the amount set forth in the applicable prospectus supplement. However, in this case the holders of preferred stock of that series will not be entitled to any other or further payment. If upon any liquidation, dissolution or winding up, our net assets are insufficient to permit the payment in full of the respective amounts to which the holders of all outstanding preferred stock are entitled, our entire remaining net assets will be distributed among the holders of each series of preferred stock in amounts proportional to the full amounts to which the holders of each series are entitled, subject to any provisions of any series of preferred stock that rank it junior or senior to other series of preferred stock upon liquidation.

Conversion, Redemption or Exchange Rights. The shares of a series of preferred stock may be convertible at the option of the holder of the preferred stock, redeemable at our option or the option of the holder, as applicable, or exchangeable at our option, into another security.

General. Our amended and restated certificate of incorporation and our amended and restated by-laws contain certain provisions that may be deemed to have an anti-takeover effect and may delay, deter or prevent a tender offer or takeover attempt that a stockholder might consider in its best interest, including those attempts that might result in a premium over the market price for the shares held by stockholders.

Our amended and restated certificate of incorporation also provides that any action required or permitted to be taken by the holders of common stock may be effected only at an annual or special meeting of such holders, and that stockholders may act in lieu of such meetings only by unanimous written consent. Our amended and restated by-laws provide that special meetings of holders of common stock may be called only by our Chairman or President or board of directors. Holders of common stock are not permitted to call a special meeting or to require that our board of directors call a special meeting of stockholders.

Our amended and restated by-laws establish an advance notice procedure for the nomination, other than by or at the direction of our board of directors, of candidates for election as directors as well as for other stockholder proposals to be considered at annual meetings of stockholders. In general, notice of intent to nominate a director or raise business at such meetings must be received by us not less than 90 nor more than 120 days prior to the date of the annual meeting and must contain certain specified information concerning the person to be nominated or the matters to be brought before the meeting and concerning the stockholder submitting the proposal.

Our amended and restated certificate of incorporation provides that certain provisions of our amended and restated by-laws may only be amended by the affirmative vote of the holders of 75% of our outstanding shares entitled to vote. Our amended and restated certificate of incorporation also provides that, in addition to any affirmative vote required by law, the affirmative vote of holders of 80% of our outstanding voting stock and two-thirds of the voting stock other than voting stock held by an interested stockholder shall be necessary to approve certain business combinations proposed by an interested stockholder.

Certain Effects of Authorized But Unissued Stock. Our authorized but unissued shares of Common Stock and preferred stock may be issued without additional stockholder approval and may be utilized for a variety of corporate purposes, including future offerings to raise additional capital or to facilitate corporate acquisitions.

The issuance of preferred stock could have the effect of delaying or preventing a change in control of us. The issuance of preferred stock could decrease the amount available for distribution to holders of our common stock or could adversely affect the rights and powers, including voting rights, of such holders. In certain circumstances, such issuance could have the effect of decreasing the market price of our Common Stock.

One of the effects of the existence of unissued and unreserved Common Stock or preferred stock may be to enable our board of directors to issue shares to persons friendly to current management, which could render more difficult or discourage an attempt to obtain control of us by means of a merger, tender offer, proxy contest or otherwise, and thereby protect the continuity of management. Such additional shares also could be used to dilute the stock ownership of persons seeking to obtain control of us.

We are subject to the “business combination” statute of the DGCL. In general, such statute prohibits a publicly held Delaware corporation from engaging in a “business combination” with any “interested stockholder” for a period of three years after the date of the transaction in which the person became an “interested stockholder,” unless:

A “business combination” includes mergers, asset sales and other transactions resulting in financial benefit to the “interested stockholder.” An “interested stockholder” is a person who, together with affiliates and associates, owns (or within three years, did own) beneficially 15% or more of a corporation’s voting stock. The statute could prohibit or delay mergers or other takeover or change in control attempts with respect to us and, accordingly, may discourage attempts to acquire us.



	•		the title and liquidation preference per share of the preferred stock and the number of shares offered;



	•		the dividend rate (or method of calculation), the dates on which dividends will be payable, whether dividends shall be cumulative and, if so, the date from which dividends will begin to accumulate;



	•		any redemption or sinking fund provisions of the preferred stock;



	•		any conversion, redemption or exchange provisions of the preferred stock;



	•		any additional dividend, liquidation, redemption, sinking fund and other rights, preferences, privileges, limitations and restrictions of the preferred stock.


(1)	such transaction is approved by our board of directors prior to the date the interested stockholder obtains such status,


(3)	the “business combination” is approved by our board of directors and authorized at an annual or special meeting of stockholders by the affirmative vote of at least 66-2/3% of the outstanding voting stock which is not owned by the “interested stockholder.”