Exhibit 99(a)(xvii)

LORD ABBETT SECURITIES TRUST

AMENDMENT TO

DECLARATION AND AGREEMENT OF TRUST

          The undersigned, being at least a majority of the Trustees of the Lord Abbett Securities Trust, a Delaware statutory trust (the “Trust”) organized pursuant to a Declaration and Agreement of Trust dated February 26, 1993 (the “Declaration”), do hereby establish, pursuant to Section 5.3 of the Declaration, a new class of shares for the series of the Trust named Lord Abbett Growth Leaders Fund, to be designated as Class B shares of such series. Any variations between the new class and the existing classes of the Trust as to purchase price, determination of net asset value, the price, terms and manner of redemption, special and relative rights as to dividends and on liquidation, and conditions under which such classes shall have separate voting rights, shall be set forth in the Declaration or elsewhere determined by the Board of Trustees of the Trust.

          This instrument shall constitute an amendment to the Declaration.

          IN WITNESS WHEREOF, the undersigned have executed this instrument this 13^th day of September, 2012.

/s/Robert S. Dow	/s/Daria L. Foster
Robert S. Dow	Daria L. Foster
/s/E. Thayer Bigelow	/s/Robert B. Calhoun, Jr.
E. Thayer Bigelow	Robert B. Calhoun, Jr.
/s/Evelyn E. Guernsey	/s/Julie A. Hill
Evelyn E. Guernsey	Julie A. Hill
/s/Franklin W. Hobbs	/s/Thomas J. Neff
Franklin W. Hobbs	Thomas J. Neff
/s/James L.L. Tullis
James L.L. Tullis