Execution Copy EXHIBIT 2.1 AGREEMENT AND PLAN OF MERGER Dated as of August 28, 2001 By and Among ALLIED RISER COMMUNICATIONS CORPORATION, COGENT COMMUNICATIONS GROUP, INC.Agreement and Plan of Merger • October 17th, 2001 • Allied Riser Communications Corp • Telephone communications (no radiotelephone) • Delaware
Contract Type FiledOctober 17th, 2001 Company Industry Jurisdiction
EXHIBIT 2.1 Certain confidential portions of this Exhibit were omitted by means of blackout of the text (the "Mark"). This Exhibit has been filed separately with the Secretary of the Commission without the Mark pursuant to the Company's Application...Agreement and Plan of Merger • February 16th, 1999 • Earthweb Inc • Services-computer processing & data preparation • New York
Contract Type FiledFebruary 16th, 1999 Company Industry Jurisdiction
EXHIBIT 2.1 AGREEMENT AND PLAN OF RESTRUCTURING AND MERGERAgreement and Plan of Merger • July 6th, 1998 • At&t Corp • Telephone communications (no radiotelephone) • Delaware
Contract Type FiledJuly 6th, 1998 Company Industry Jurisdiction