13D Filing: Energy Spectrum Securities Corp and American Midstream Partners, Lp (AMID)

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

SCHEDULE 13D/A

(Rule 13d-101)

Under the Securities Exchange Act of
1934

(Amendment No. 1)

American
Midstream Partners, LP

(Name of Issuer)

Common
Units

(Title of Class of Securities)

02752P100

(CUSIP Number)

James
P. Benson, 5956 Sherry Lane, Suite 900

Dallas, TX 75225, (214) 987-6100

(Name, Address and Telephone Number of Person

Authorized to Receive Notices and Communications)

February
16, 2016

(Date of Event which Requires Filing

of this Statement)

If the filing person has previously filed
a statement on Schedule 13G to report the acquisition which is the subject of this Schedule 13D, and is filing this schedule because
of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box ¨.

The information required on 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 (the “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).

Page 1 of 10

*          Based
on the 30,425,829 common units of the Issuer (“Common Units”) outstanding as of November 6, 2015, as reported
in the Issuer’s Quarterly Report on Form 10-Q filed on November 9, 2015.

*          Based
on the 30,425,829 Common Units outstanding as of November 6, 2015, as reported in the Issuer’s Quarterly Report on
Form 10-Q filed on November 9, 2015.

*          Based on the 30,425,829
Common Units outstanding as of November 6, 2015, as reported in the Issuer’s Quarterly Report on Form 10-Q filed on
November 9, 2015.

*          Based
on the 30,425,829 Common Units outstanding as of November 6, 2015, as reported in the Issuer’s Quarterly Report on
Form 10-Q filed on November 9, 2015.

*          Based
on the 30,425,829 Common Units outstanding as of November 6, 2015, as reported in the Issuer’s Quarterly Report on Form
10-Q filed on November 9, 2015.

This statement on this
Amendment No. 1 to Schedule 13D amends and supplements the Statement on Schedule 13D filed on October 14, 2014 (as amended, this
“Schedule 13D”), filed with respect to common units (“Common Units”) of American Midstream Partners, LP
(the “Issuer”). The Issuer’s principal executive offices are located at 1400 16th Street, Suite 310, Denver,
CO 80202.

Item 2 is hereby amended
and restated in its entirety as follows:

The persons filing
this statement are Energy Spectrum Securities Corporation, a Texas corporation whose principal businesses are providing, through
affiliates, private equity capital to businesses engaged in the exploration, development, production, gathering, transportation,
processing, treatment, and storage of oil and natural gas and related hydrocarbons and the provision of financial advisory services
to energy industry participants (“ESSC”), Energy Spectrum VI, LLC, a Texas limited liability company whose principal
business is serving as the general partner of ESCLP (“ESLLC”), Energy Spectrum Capital VI LP, a Delaware limited partnership
whose principal business is serving as the general partner of ESP (“ESCLP”), Energy Spectrum Partners VI LP, a Delaware
limited partnership whose principal business is providing private equity capital to businesses engaged in the gathering, transportation,
processing, treatment, and storage of oil and natural gas and related hydrocarbons (“ESP”, and together with ESSC,
ESLLC, and ESCLP, the “Energy Spectrum Entities”), and Costar Midstream Energy LLC whose principal business is holding
and disposing of a portion of the Subject Units (as subsequently defined) (“CME” and collectively with the Energy Spectrum
Entities, the “Reporting Persons”). The principal business address of the Energy Spectrum Entities is 5956 Sherry
Lane, Suite 900, Dallas, TX 75225. The principal business address of CME is 1313 North Trail, Carrolton, Texas 75006.

ESSC is the sole member
of ESLLC, which is the sole general partner of ESCLP, which is the sole general partner of ESP. The directors and executive officers
of ESSC are Thomas O. Whitener, Leland B. White, James P. Benson, and James W. Spann (the “Directors”). Thomas O. Whitener,
Leland B. White, James P. Benson, and James W. Spann serve as the managers of ESLLC (the “ESLLC Managers”) and James
P. Benson serves as the manager of CME (the “CME Manager” and together with the Directors and the ESLLC Managers, the
“Management Persons”). The business address of the Directors and the ESLLC Managers is the same as that of ESSC. The
principal occupation of each of the Directors is serving as Directors and officers of ESSC and managing its portfolio companies
and partnerships.

The Reporting Persons
and the Management Persons, during the last five years, have not been convicted in a criminal proceeding (excluding traffic violations
or similar misdemeanors).The Reporting Persons and each of the Management Persons, during the last five years, have not
been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction or subject to a judgment, decree
or final order enjoining future violations of, or prohibiting or mandating activities subject to federal or state securities laws
or finding any violation with respect to such laws. Each of the Management Persons is a citizen of the United States of America.

Item 3 is hereby amended
and restated in its entirety as follows:

The 5,393,615
Common Units (the “Subject Units”) reported on this Schedule 13D are owned directly by ESP and CME and were acquired
by each of ESP and CME pursuant to the terms of that certain Purchase and Sale Agreement (the “Purchase Agreement”)
dated October 13, 2014, by and among ESP, CME and American Midstream, LLC, a Delaware limited liability company and wholly owned
subsidiary of the Issuer (“AMID”), as part of the consideration received by ESP and CME in exchange for their sale
of 100% of the membership interest of Costar Midstream, L.L.C., a Texas limited liability company (“Costar”) to AMID.

Under the terms of
the Purchase Agreement and pursuant to the terms of that certain Irrevocable Letter, dated October 14, 2014, signed by the Issuer
directing its transfer agent to issue the Subject Units to ESP and CME, directly and in escrow, on November 8, 2014 (the “Irrevocable
Letter”), ESP and CME obtained beneficial ownership of the Subject Units as of October 14, 2014, and record ownership of
the Subject Units on November 8, 2014 upon issuance thereof pursuant to the terms of the Irrevocable Letter. In connection with
the consummation of the transactions contemplated in the Purchase Agreement, ESP, CME and the Issuer entered into that certain
Securities Agreement dated as of October 14, 2014 by and among ESP, CME, and the Issuer (the “Securities Agreement”),
pursuant to which, among other things, the Subject Units are subject to restrictions on sale by ESP and CME. Copies of the Securities
Agreement and the Purchase Agreement are attached to that certain Schedule 13D of the Reporting Persons, filed October 14, 2014,
as Exhibits 99.2 and 99.5, respectively and are incorporated herein by reference. As a result of the transactions contemplated
in the Purchase Agreement and a reallocation of Common Units among ESP and CME to account for their respective satisfaction of
transaction related liabilities, ESP and CME held record and beneficial ownership of 6,188,326 Common Units and 704,605 Common
Units, respectively (237,341 of which were held by CME and the subject of shared dispositive power). 1,379,311 of these Common
Units were held in escrow, pursuant to the terms of an Escrow Agreement, dated October 14, 2014, by and among AMID, ESP, CME, and
Wells Fargo Bank National Association, a copy of which is attached to that certain Schedule 13D of the Reporting Persons, filed
October 14, 2014, as Exhibit 99.4, and is incorporated herein by reference (the “Escrow Agreement”). Pursuant to the
Escrow Agreement, the Common Units held in the escrow were subject to release to AMID for the satisfaction of certain indemnity
claims under the Purchase Agreement. Effective August 4, 2015, 278,137 Common Units and 66,691 Common Units were released to ESP
and CME, respectively, from the escrow established by the Escrow Agreement. On September 24, 2015, and October 24, 2015, CME distributed
210,899 Common Units and 253,934 Common Units, respectively, to its equity owners, none of whom are Reporting Persons.

On February 12, 2016,
AMID, ESP and CME entered into that certain Settlement and Mutual Release Agreement, dated February 12, 2016, whereby among other
transactions, the 1,034,483 Common Units remaining in the escrow established pursuant to the Escrow Agreement were released to
the Issuer, and ESP and CME released all claims thereto.

Item 4 is hereby amended
by restating the first paragraph thereof as follows:

The Reporting Persons
acquired the Subject Units pursuant to the transactions contemplated in the Purchase Agreement and currently expect to sell the
Subject Units from time to time as market conditions warrant, subject to the terms of the Securities Agreement. The Management
Persons do not have a direct or indirect beneficial ownership interest in the Issuer.

Items 5(a) and (b)
are hereby amended and restated in their entireties as follows:

(a) As of the date
hereof, the Energy Spectrum Entities may be deemed to be the direct or indirect beneficial owners of 5,393,615
Common Units, representing approximately 17.72% of the Issuer’s outstanding Common Units, of which 5,353,915 are owned
of record by ESP, representing approximately 17.59% of the Issuer’s outstanding Common Units. The shares beneficially owned
by CME consist of 39,700 Common Units, representing approximately 0.13% of the Issuer’s outstanding Common Units, of which
all are owned of record by CME. The Energy Spectrum Entities may be deemed to be indirect beneficial owners of the 39,700 Common
Units owned by CME by virtue of James P. Benson serving as the manager of CME. In both cases the calculation of beneficial ownership
percentage is based on a total number of issued and outstanding Common Units of 30,425,829
(which is the number of shares listed as outstanding under the Issuer’s most recent 10-Q). The Management Persons
do not beneficially own any Common Units.

Other than as set forth
above, the Reporting Persons and Management Persons are not the beneficial owners of any Common Units individually.

(b) The Energy Spectrum
Entities have sole power to vote and dispose of 5,393,615 Common Units and shared
power to vote and dispose of 39,700 Common Units, which power is shared with CME.

No changes or amendments
to Item 6.

No changes or amendments
to Item 7.

SIGNATURES

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

Date: February 23, 2016