	UNITED STATES	OMB APPROVAL
	SECURITIES AND EXCHANGE COMMISSION	OMB Number: 3235-0145
	Washington, D.C. 20549	Expires: December 31, 2005
	SCHEDULE 13G	Estimated average burden hours per response. . 11

Under the Securities Exchange Act of 1934
(Amendment No. 2)*

Guidant Corp.

(Name of Issuer)

Common

(Title of Class of Securities)

401698105

(CUSIP Number)

Check the following box if a fee is being paid with this statement o. (A fee is not required only if the filing person: (1) has a previous statement on file reporting beneficial ownership of more than five percent of the class of securities described in Item 1; and (2) has filed no amendment subsequent thereto reporting beneficial ownership of five percent or less of such class.) (See Rule 13d-7).

*The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 401698105

	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) PRIMECAP Management Company 95-3868081

	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)		[ ]
		(b)		[ ]

	3.	SEC Use Only

	4.	Citizenship or Place of Organization 225 South Lake Avenue #400, Pasadena, CA 91101

Number of Shares Beneficially Owned by Each Reporting Person With			5.		Sole Voting Power 2,813,663

			6.		Shared Voting Power -0-

			7.		Sole Dispositive Power 18,802,963

			8.		Shared Dispositive Power -0-

	9.	Aggregate Amount Beneficially Owned by Each Reporting Person 18,802,963

	10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ]

	11.	Percent of Class Represented by Amount in Row (9) 5.99%

	12.	Type of Reporting Person (See Instructions) IA

Item 8.	Identification and Classification of Members of the Group
If a group has filed this schedule pursuant to Rule 13d-1(b)(ii)(H), so indicate under Item 3(h) and attach an exhibit stating the identity and Item 3 classification of each member of the group. If a group has filed this schedule pursuant to Rule 13d-1(c), attach an exhibit stating the identity of each member of the group.

Item 9.	Notice of Dissolution of Group
Notice of dissolution of a group may be furnished as an exhibit stating the date of the dissolution and that all further filings with respect to transactions in the security reported on will be filed, if required, by members of the group, in their individual capacity. See Item 5.

Item 10.	Certification
The following certification shall be included if the statement is filed pursuant to Rule 13d-1(b):
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired in the ordinary course of business and were not acquired for the purpose of and do not have the effect of changing or influencing the control of the issuer of such securities and were not acquired in connection with or as a participant in any transaction having such purposes or effect.

Signature

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

	June 30, 2004
	Date
	/s/ Theo A. Kolokotrones
	Signature
	Theo A. Kolokotrones, President
	Name/Title