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SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 4 )*
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Tandem Computers, Inc.
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(Name of Issuer)
Common
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(Title of Class of Securities)
875370108
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(CUSIP Number)
Check the following box if a fee is being paid with this statement / /. (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 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).
(Continued on following page(s))
Page 1 of 5 Pages
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CUSIP No. 875370108 13G
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(1) Names of Reporting Persons. S.S. or I.R.S. Identification Nos. of Above
Persons
PRIMECAP Management Company 95-3868081
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(2) Check the Appropriate Box if a Member (a) / /
of a Group* (b) / /
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(3) SEC Use Only
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(4) Citizenship or Place of Organization
225 So. Lake Avenue #400, Pasadena, CA 91101-3005
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Number of Shares (5) Sole Voting
Beneficially Power 5,634,000
Owned by --------------------------------------------------
Each Reporting (6) Shared Voting
Person With Power -0-
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(7) Sole Dispositive
Power 5,634,000
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(8) Shared Dispositive
Power -0-
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(9) Aggregate Amount Beneficially Owned by Each Reporting Person
5,634,000
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(10) Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares*
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(11) Percent of Class Represented by Amount in Row (9)
4.87%
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(12) Type of Reporting Person*
IA
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*SEE INSTRUCTION BEFORE FILLING OUT!
Page 2 of 5 Pages
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ITEM 1(A). NAME OF ISSUER
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ITEM 1(B). ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES
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ITEM 2(A). NAME OF PERSON(S) FILING
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ITEM 2(B). ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE
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ITEM 2(C). CITIZENSHIP
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ITEM 2(D). TITLE OF CLASS OF SECURITIES
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ITEM 2(E). CUSIP NUMBER
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ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO RULES 13D-1(B), OR 13D-2(B),
CHECK WHETHER THE PERSON FILING IS A
(a) / / Broker or Dealer registered under Section 15 of the Act
(b) / / Bank as defined in section 3(a)(6) of the Act
(c) / / Insurance Company as defined in section 3(a)(19) of the Act
(d) / / Investment Company registered under section 8 of the Investment
Company Act
(e) / / Investment Adviser registered under section 203 of the Investment
Advisers Act of 1940
(f) / / Employee Benefit Plan, Pension Fund which is subject to the
provisions of the Employee Retirement Income Security Act of 1974
or Endowment Fund; see Rule 13d-1(b)(1)(ii)(F)
(g) / / Parent Holding Company, in accordance with Rule 13d-1(b)(ii)(G)
(Note: See Item 7)
(h) / / Group, in accordance with Rule 13d-1(b)(1)(ii)(H)
Page 3 of 5 Pages
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ITEM 4. OWNERSHIP
(a) Amount Beneficially Owned:
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(b) Percent of Class:
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(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote
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(ii) shared power to vote or to direct the vote
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(iii) sole power to dispose or to direct the disposition of
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(iv) shared power to dispose or to direct the disposition of
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INSTRUCTION: For computations regarding securities which represent a right to
acquire an underlying security see Rule 13d-3(d)(l).
ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS
If this statement is being filed to report the fact that as of the date hereof
the reporting person has ceased to be the beneficial owner of more than five
percent of the class of securities, check the following /X/.
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INSTRUCTION: Dissolution of a group requires a response to this item.
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON
If any other person is known to have the right to receive or the power
to direct the receipt of dividends from, or the proceeds from the sale of,
such securities, a statement to that effect should be included in response to
this item and, if such interest relates to more than five percent of the
class, such person should be identified. A listing of the shareholders of an
investment company registered under the Investment Company Act of 1940 or the
beneficiaries of employee benefit plan, pension fund or endowment fund is not
required.
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ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED
THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY
If a parent holding company has filed this schedule, pursuant to Rule
13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating
the identity and the Item 3 classification of the relevant subsidiary. If a
parent holding company has filed this schedule pursuant to Rule 13d-1(c),
attach an exhibit stating the identification of the relevant subsidiary.
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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.
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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.
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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.
August 21, 1997
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Date
/s/ Theo A. Kolokotranes, President
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Signature
Theo A. Kolokotranes, President
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Name/Title
Page 4 of 5
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The original statement shall be signed by each person on whose behalf
the statement is filed or his authorized representative. If the statement is
signed on behalf of a person by his authorized representative other than an
executive officer or general partner of the filing person, evidence of the
representative's authority to sign on behalf of such person shall be filed
with the statement, provided, however, that a power of attorney for this
purpose which is already on file with the Commisssion may be incorporated by
reference. The name and any title of each person who signs the statement
shall be typed or printed beneath his signature.
NOTE: Six copies of this statement, including all exhibits, should be filed
with the Commission.
ATTENTION: INTENTIONAL MISSTATEMENTS OR OMISSIONS OF FACT CONSTITUTE
FEDERAL CRIMINAL VIOLATIONS (SEE 18 U.S.C. 1001)
Page 5 of 5
