UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549
Under the Securities and Exchange Act of 1934
(Amendment No. 3 )
MORRISON KNUDSEN CORP
(Name of Issuer)
Common
(Title of Class of Securities)
Date of Event Which Requires Filing of this Statement
August 20, 1999
Check the appropriate box to designate the rule
pursuant to which this Schedule is filed
X Rule 13d-2(b)
61844A109
(CUSIP NUMBER)
Page 1 of 5
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1 Name of Reporting Pioneer
Person Investment
IRS Identification Management Inc.
No. of Above 13-1961193
(a/k/a/ Pioneering
Management Corp.)
2) Check the Appropriate Box (a)
of A Member of Group
(See Instructions) (b) X
3 SEC Use Only
4 Citizenship of Place of
Organization Delaware
Number of (5) Sole Voting 1496500
Shares Power
Beneficially Owned (6) Shared Voting 0
by Each Reporting Power
Person With (7) Sole Dispositive 1496500
Power
(8) Shared 0
Dispositive
Power
9 Aggregate Amount Beneficially 1496500
Owned by Each
Reporting Person
10 Check if the aggregate
Amount in Row (9) Exclude Certain
Shares (See
Instructions)
11 Percent of Class Represented
By Amount in Row 9. 2.82%
12 Type of Reporting
Person (See Instructions) IA
Page 2 of 5
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Item 1(a) Name of Issuer.
MORRISON KNUDSEN CORP
Item 1(b) Address of Issuer's Principal Executive Office's
One Morrison Knudsen Plaza
720 Park Boulevard
Boise, ID 83729
Item 2(a) Name of Person Filing.
Pioneer Investment Management, Inc. a/k/a/
Pioneering Management Corporation
Item 2(b) Address of Principal Business Office:
60 State Street, Boston, MA 02109
Item 2(c) Citizenship:
State of Delaware
Pioneer Investment Management a/k/a
Pioneering Management Corporation
Item 2(d) Title of Class of Securities.
Common Stock
Item 2(e) CUSIP Number.
61844A109
Item 3 The person filing this statement pursuant to Rule 13-1(b)
or 13(d)-2(b) or (c) is a:
(e) Investment Adviser registered under Section 203 of
the Investment Advisers Act of 1940.
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Item 4. Ownership
(a) Amount Beneficially Owned 1496500
(b) Percent of Class 2.82%
(c) Number of shares as to which such person has
(i) sole power to vote or to direct the vote 1496500
(ii) shared power to vote or to direct vote 0
(iii) sole power to dispose or to direct disposition of 1496500
(iv) shared power to dispose or to direct disposition 0
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 here: X
Item 6. Ownership of More than Five Percent on Behalf of Another Person.
Inapplicable.
Item 7. Identification and Classification of the Subsidiary Which Acquired
the Security Being Reported On By the Parent Holding Company.
Inapplicable.
Item 8. Identification and Classification of Members of the Group.
Inapplicable.
Item 9. Notice of Dissolution of the Group.
Inapplicable.
Page 4 of 5 pages
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Item 10. Certification.
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 transactions having
such purposes or effect.
After reasonable inquiry and to the best of my knowledge and believe, I
certify that the information set forth in this statement is true, complete and
correct.
August 20, 1999
Date
/s/Robert P. Nault
Signature
Robert P. Nault
Assistant Secretary
Type Name and Title
Page 5 of 5