Addendum to Management Agreement between Lord Abbett Securities Trust and Lord, Abbett & Co. LLC Dated: June 15, 2011 (the “Addendum”)

Addendum to Management Agreement between

Lord Xxxxxx Securities Trust

and

Lord, Xxxxxx & Co. LLC

Dated: June 15, 2011 (the “Addendum”)

Lord, Xxxxxx & Co. LLC (“Lord Xxxxxx”) and Lord Xxxxxx Securities Trust (the “Trust”), on behalf of its Lord Xxxxxx Growth Leaders Fund (the “Fund”), do hereby agree that the annual management fee rate for the Fund with respect to paragraph 2 of the management agreement dated May 19, 1993 (“Management Agreement”), shall be as follows: 0.55 of 1% of the first $2 billion of the Fund’s average daily net assets; and 0.50 of 1% of such assets in excess of $2 billion.

For purposes of Section 15(a) of the Act, this Addendum, together with the Management Agreement and addenda thereto insofar as they have not been superseded, shall together constitute the investment advisory contract of the Trust.

LORD XXXXXX SECURITIES TRUST

/s/ Xxxxxx X. Xxxxxxxx

Xxxxxx X. Xxxxxxxx

Vice President and Assistant Secretary

LORD, XXXXXX & CO. LLC

/s/ Xxxxxxxx X. Xxxxxx

Xxxxxxxx X. Xxxxxx

Member and General Counsel