a member of the Certegy Group at the expense of the Equifax Group. Certegy hereby assigns, and shall cause each member of the Certegy Group to assign, to Equifax, or the respective Designated Equifax Member, all right, title and interest it may hold in and to such modifications, improvements, Equifax Enhancements and Derivative Works. Equifax shall, or shall cause the respective Designated Equifax Member to, have the right to make and file all applications and other documents required to register the copyright(s) and file for patents for such modifications, improvements, Equifax Enhancements and Derivative Works in its discretion and at its sole cost and expense. (b) Should Equifax elect to file any application for the registration, perfection or protection of any modifications, improvements, Equifax Enhancements or Derivative Works described in Section 4.5(a), under any copyright, patent or other law of any country or jurisdiction, Certegy will, at the request and expense of Equifax, do all things and sign all documents or instruments reasonably necessary in the opinion of Equifax to assist in the 17 registration of such claims, file such applications, and obtain, defend and enforce such copyright, patent, mask work and other rights. (c) Subject to the license rights granted in Section 4.4, as between the parties, the Licensed Certegy Materials shall be and shall remain the sole and exclusive property of the Certegy Group and the members of the Certegy Group may make any internal use and may commercially exploit any enhancements to the Licensed Materials made or caused to be made by members of the Equifax Group, as they shall deem appropriate without any obligation to any member of the Equifax Group or other restriction. The Certegy Group may in particular distribute and manufacture, or cause to be manufactured or distributed by any third party, any such