13D Filing: Magnolia Infrastructure Holdings, LLC and American Midstream Partners LP (AMID)

This Amendment No. 20 to Schedule 13D amends and supplements the Statement on Schedule 13D filed on
May 3, 2013, as amended by Amendment No. 1 filed on November 14, 2014, Amendment No. 2 filed on February 17, 2015, Amendment No. 3 filed on April 3, 2015, Amendment No. 4 filed on May 15, 2015, Amendment
No. 5 filed on August 18, 2015, Amendment No. 6 filed on August 19, 2015, Amendment No. 7 filed on September 17, 2015, Amendment No. 8 filed on November 18, 2015, Amendment No. 9 filed on
December 22, 2015, Amendment No. 10 filed on January 6, 2016, Amendment No. 11 filed on January 11, 2016, Amendment No. 12 filed on February 1, 2016, Amendment No. 13 filed on February 24, 2016, Amendment
No. 14 filed on April 27, 2016, Amendment No. 15 filed on May 18, 2016, Amendment No. 16 filed on November 3, 2016, Amendment No. 17 filed on December 6, 2016, Amendment No. 18 filed on March 8, 2017
and Amendment No. 19 filed on August 18, 2017 (as amended, this Schedule 13D), filed with respect to the common units representing limited partner interests (Common Units) of American Midstream Partners, LP (the
Issuer). Amendment No. 20 is being filed to report the disposition of certain securities of the Issuer by the reporting persons.

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