Ex. 99.28(d)(19)(viii)

Amendment to

Investment Sub-Advisory Agreement Between

Jackson National Asset Management, LLC

and DoubleLine Capital LP

This Amendment is made by and between Jackson National Asset Management, LLC, a Michigan limited liability company and registered investment adviser (the “Adviser”), and DoubleLine Capital LP, a Delaware limited partnership and registered investment adviser (the “Sub-Adviser”).

Whereas, the Adviser and the Sub-Adviser (the “Parties”) entered into an Investment Sub-Advisory Agreement effective as of the 28^th day of September, 2015, as amended (the “Agreement”), whereby the Adviser appointed the Sub-Adviser to provide certain sub-investment advisory services to certain investment portfolios (each a “Fund”) of JNL Series Trust (the “Trust”), as listed on Schedule A of the Agreement, for the portion of each Fund’s assets allocated to the Sub-Adviser.

Whereas, the Board of Trustees of the Trust has approved, and the Parties have agreed to amend Section 3. “Management” and Section 12. “Duration and Termination” of the Agreement, effective September 6, 2019.

Now Therefore, in consideration of the mutual covenants herein contained, the Parties hereby agree to amend the Agreement as follows:

1) Sub-paragraph h) after “The Sub-Adviser further agrees that it:”, under Section 3. “Management,” shall be deleted and replaced, in its entirety, with the following:

h) will act upon reasonable instructions from Adviser (except as to the voting of proxies) not inconsistent with the fiduciary duties and investment objectives hereunder;

2) Sub-paragraph j) after “The Sub-Adviser further agrees that it:”, under Section 3. “Management,” shall be deleted and replaced, in its entirety, with the following:

j) consistent with its fiduciary duties to each Fund and on the Fund’s behalf, the Sub-Adviser is hereby appointed the Fund’s agent to exercise in its direction all rights and performs all duties with respect to the Fund’s right to vote (or refrain from voting), each Fund’s securities and exercise rights in corporate actions or otherwise in accordance with the Sub-Adviser’s proxy voting guidelines, as amended from time to time, which shall be provided to the Trust and the Adviser. For the avoidance of doubt, the Sub-Adviser will have full discretion in this regard and the Adviser will not attempt to influence the Sub-Adviser’s voting decisions. The Sub-Adviser further agrees to report significant shareholdings for itself and on behalf of the Fund where required by local law; and may, at its discretion (subject to Sub-Adviser’s responsibility and liability under the terms of this Sub-Advisory Agreement), elect to use one or more third parties, including proxy voting services, in fulfilling its obligations hereunder; provided however, Adviser will, or will direct the Fund’s custodian to, send all proxy solicitation material and other related material, including interim reports, annual reports and other issuer mailings with respect to the Account, to Sub-Adviser or its agent;

3) Section 12. “Duration and Termination” shall be deleted and replaced, in its entirety, with the following:

Duration and Termination. The Agreement will become effective as to a Fund upon execution or, if later, on the date that initial capital for such Fund is first provided to it and, unless sooner terminated as provided herein, the initial term will continue in effect through September 30, 2016.  Hereafter, if not terminated as to a Fund, this Agreement will continue from year to year through September 30^th for each Fund covered by this Agreement, as listed on Schedule A, provided that such continuation is specifically approved at least annually by the Trust’s Board of Trustees or by vote of a majority of the outstanding voting securities of such Fund(s), and in either event approved also by a

majority of the Trustees of the Trust who are not interested persons of the Trust, or of the Adviser, or of the Sub-Adviser (“Independent Trustees”). Notwithstanding the foregoing, this Agreement may be terminated as to a Fund at any time, without the payment of any penalty, by the Board, including a majority of the Independent Trustees, or by the vote of a majority of the outstanding voting securities of each Fund, on sixty days’ written notice to the Adviser and the Sub-Adviser, or by the Adviser with the consent of the Board (including a majority of the Independent Trustees), or on sixty days’ written notice by the Sub-Adviser to the Trust and the other party.  This Agreement will immediately terminate in the event of its assignment.  (As used in this Agreement, the terms “majority of the outstanding voting securities”, “interested persons” and “assignment” have the same meaning of such terms as in the 1940 Act.)  Section 10 and 11 herein shall survive the termination of this Agreement.

In the event of termination, Adviser or Trust will remain liable to Sub-Adviser for any sub-advisory fees incurred pursuant to Section 8 above through termination, until the Sub-Adviser discontinues trading or the funds have been withdrawn from the Sub-Adviser’s management, whichever is earliest.

4) Except as specifically amended hereby, the Agreement shall remain in full force and effect in accordance with its terms.

5) Each of the Parties represents and warrants to the others that it has full authority to enter into this Amendment upon the terms and conditions hereof and that the individual executing this Amendment is duly authorized to bind the respective party to this Amendment.

6) This Amendment may be executed in one or more counterparts, which together shall constitute one document.

In Witness Whereof, the Parties have caused this Amendment to be executed, effective September 6, 2019.

Jackson National Asset Management, LLC		DoubleLine Capital LP
By:	/s/ Mark D. Nerud	By:	/s/ Ronald Redell
Name:	Mark D. Nerud	Name:	Ronald Redell
Title:	President and CEO	Title:	Authorized Signer

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