EXHIBIT 99.5 PROXY McKESSON CORPORATION PROXY FOR SPECIAL MEETING 10:00 A.M., JANUARY 12, 1999 SOLICITED ON BEHALF OF THE BOARD OF DIRECTORS OF THE CORPORATION The undersigned, whose signature appears on the reverse side, hereby constitutes and appoints Mark A. Pulido, Ivan D. Meyerson and Nancy A. Miller, and each of them, with full power of substitution, proxies to vote all of the shares of common stock of McKesson Corporation which the undersigned is entitled to vote at the Special Meeting of Stockholders to be held at The Palace Hotel, 2 New Montgomery Street, San Francisco, California, on January 12, 1999, and any adjournments thereof, as specified upon the matter indicated on the reverse side. You are urged to specify your voting preference by marking the appropriate box, SEE REVERSE SIDE, but you need not mark any box if you wish to vote in accordance with the Board of Directors' recommendation. The above named proxies cannot vote your shares unless you (1) vote by telephone as described on the reverse side, or (2) sign and return this card. ----------- SEE REVERSE SIDE ----------- YOUR VOTE IS IMPORTANT YOU CAN VOTE IN ONE OF TWO WAYS: 1. Call toll free as described in the instructions on the reverse side. There is NO CHARGE to you for this call, if calling from the United States, Canada, Puerto Rico and the U.S. Virgin Islands. or -- 2. Mark, sign and date your proxy card and return it promptly in the enclosed business reply envelope. PLEASE VOTE PLEASE MARK YOUR 4896 [X] VOTE AS IN THIS EXAMPLE. THIS PROXY WHEN PROPERLY EXECUTED WILL BE VOTED IN THE MANNER DIRECTED BELOW. IF NO DIRECTION IS GIVEN, THIS PROXY WILL BE VOTED FOR THE FOLLOWING PROPOSAL. - -------------------------------------------------------------------------------- THE BOARD OF DIRECTORS RECOMMENDS A VOTE FOR THE FOLLOWING PROPOSAL: - -------------------------------------------------------------------------------- FOR AGAINST ABSTAIN [_] [_] [_] 1. Approval of the Agreement and Plan of PLEASE CAST YOUR VOTE BY Merger, dated as of October 17, 1998, TELEPHONE AS INSTRUCTED as amended as of November 9, 1998 BELOW OR COMPLETE, DATE, (the "Merger Agreement"), by and SIGN AND MAIL THIS PROXY among McKesson Corporation ("McKesson"), PROMPTLY IN THE ENCLOSED McKesson Merger Sub, Inc., a newly BUSINESS REPLY ENVELOPE. formed, wholly owned subsidiary of McKesson ("Merger Sub") and HBO & Company ("HBOC"), and the transactions associated with the Merger Agreement, including the issuance of shares of commmon stock, par value $0.01 per share, of McKesson in the merger of Merger Sub with and into HBOC and the change of McKesson's corporate name to "McKesson HBOC, Inc.", all in accordance with the Merger Agreement. Signature_____________________(Signature, if held jointly)_____________________Date:_____, 199_ PLEASE SIGN EXACTLY AS NAME APPEARS HEREON. JOINT OWNERS SHOULD EACH SIGN. WHEN SIGNING AS ATTORNEY, EXECUTOR, ADMINISTRATOR, TRUSTEE OR GUARDIAN, PLEASE GIVE FULL TITLE AS SUCH. - -------------------------------------------------------------------------------- FOLD AND DETACH HERE - IF YOU ARE RETURNING YOUR PROXY CARD BY MAIL VOTE BY TELEPHONE QUICK & EASY McKESSON encourages stockholders to take advantage of a new cost-effective and convenient way to vote their shares - by telephone. You may vote by telephone 24 hours a day, 7 days a week. To access the telephone voting system, you must use a touch-tone telephone and follow the instructions below: . Stockholders calling from the United States, Canada, Puerto Rico and the U.S. Virgin Islands may dial toll-free 1-800-652-8683 (1-800-OK2-VOTE). If you call from other locations, you may dial 201-324-0377, and you will bear the normal cost of international telephone access charges to use the telephone voting service. . When requested, enter the last 4 digits of your U.S. Social Security Number (if you have one) and your Voter Control Number printed in the box above, just below the perforation. . The instructions will lead you through the simple voting process. TELEPHONE VOTING PROVIDES THE SAME AUTHORIZATION TO VOTE YOUR SHARES AS IF YOU MARKED, SIGNED, DATED AND RETURNED THE PROXY CARD. IF YOU VOTE BY TELEPHONE, PLEASE DO NOT MAIL YOUR PROXY CARD. THANK YOU FOR VOTING.