<PAGE>
As filed with the Securities and Exchange Commission on September 2, 1997
Registration No. 333-26233
================================================================================
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
_______________
POST-EFFECTIVE AMENDMENT NO. 1
TO
FORM S-1
REGISTRATION STATEMENT
UNDER THE SECURITIES ACT OF 1933
_______________
MARKWEST HYDROCARBON, INC.
(Exact name of registrant as specified in its charter)
<TABLE>
<CAPTION>
<S> <C> <C>
DELAWARE 4924 84-1352233
(State or jurisdiction of (Primary Standard Industrial (I.R.S. Employer
incorporation or organization) Classification Code Number) Identification No.)
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5613 DTC PARKWAY, SUITE 400
ENGLEWOOD, COLORADO 80111
(303) 290-8700
(Address, including zip code, and telephone number, including
area code, of registrant's principal executive offices)
_______________
BRIAN T. O'NEILL
SENIOR VICE PRESIDENT AND CHIEF OPERATING OFFICER
MARKWEST HYDROCARBON, INC.
5613 DTC PARKWAY, SUITE 400
ENGLEWOOD, COLORADO 80111
(303) 290-8700
(Name, address, including zip code, and telephone number, including area code,
of agent for service)
_______________
COPIES OF COMMUNICATIONS TO:
GEORGE A. HAGERTY, ESQ.
DORSEY & WHITNEY LLP
REPUBLIC PLAZA BLDG., SUITE 4400
DENVER, COLORADO 80202
(303) 629-3400
_______________
Approximate date of commencement of proposed sale to the public:
If any of the securities being registered on this Form are to be offered on
a delayed or continuous basis pursuant to Rule 415 under the Securities Act of
1933, as amended (the "Securities Act") check the following box. [ ]
If this Form is filed to register additional securities for an offering
pursuant to Rule 462(b) under the Securities Act, please check the following box
and list the Securities Act registration statement number of the earlier
effective registration statement for the same offering. [ ]
If this Form is a post-effective amendment filed pursuant to Rule 462(c)
under the Securities Act, check the following box and list the Securities Act
registration statement number of the earlier effective registration statement
for the same offering. [ ]
If delivery of the prospectus is expected to be made pursuant to Rule 434,
please check the following box. [ ]
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Deregistration of Unsold Shares of Common Stock
-----------------------------------------------
Pursuant to this Post-Effective Amendment No. 1, MarkWest Hydrocarbon, Inc.
(the "Company") hereby deregisters the remaining 45,703 Shares of the Company's
Common Stock which were registered with the Securities and Exchange Commission
pursuant to the Company's Registration Statement on Form S-1 (File No. 333-
26233) and which were not sold pursuant to such Registration Statement. As
disclosed in such Registration Statement, the Company agreed to file and
maintain a shelf registration statement relating to the Shares registered
thereby in order to permit certain stockholders to resell such Shares from time
to time during a period of at least 60 days from April 30, 1997, the date of the
Prospectus. Such shares are being deregistered because said 60-day period, as
extended in the sole discretion of the Company, has elapsed.
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SIGNATURES
Pursuant to the requirements of the Securities Act of 1933, the registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-1 and has duly caused this Post-Effective
Amendment No. 1 to the Registration Statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of Englewood, State of
Colorado, on September 2, 1997.
MARKWEST HYDROCARBON, INC.
By: /s/ John M. Fox
-------------------------------------
John M. Fox
President and Chief Executive Officer
Pursuant to the requirements of the Securities Act of 1933, this Post-
Effective Amendment No. 1 to the Registration Statement has been signed by the
following persons in the capacities indicated on September 2, 1997.
SIGNATURE TITLE
--------- -----
/s/ John M. Fox President and
- --------------------------------- Chief Executive Officer
John M. Fox (Principal Executive Officer)
/s/ Brian T. O'Neill Senior Vice President, and
- --------------------------------- Chief Operating Officer
Brian T. O'Neill
/s/ Gerald A. Tywoniuk Vice President of Finance
- --------------------------------- and Chief Financial Officer
Gerald A. Tywoniuk (Principal Financial and
Accounting Officer)
* Senior Vice President of Engineering and
- --------------------------------- Project Management
Arthur J. Denney
* Director
- ---------------------------------
Norman H. Foster
* Director
- ---------------------------------
Barry W. Spector
* Director
- ---------------------------------
David R. Whitney
*By: /s/ Brian T. O'Neill
----------------------------------
Brian T. O'Neill, Attorney-in-Fact
