In one of the largest relocation leases signed in the Brickell Financial District in more than two years, Pittsburgh-based Mellon Financial Corp. leased 50,000 square feet at 1111 Brickell Avenue for a term of eight years. The lease has an estimated value of $11.78 million. Mellon will move 100 employees from its 20-year location at 1399 SW First Ave. to 1111 Brickell where it will occupy the 29th and 30th floors by the end of the first quarter of 2003. Former tenant and building namesake Barclay's relocated its South Florida operations to New York. Two Insignia executives, Senior Managing Director Randy Olen and Executive Director of International Client Services Stuart Eisenkraft, negotiated the Barclay's sublease.