In general terms, the project aims to renovate the civil infrastructure and stations of Metro Line 3, as well as to rehabilitate the track, electrical, electronic, mechanical, and accessibility systems for persons with reduced mobility, in addition to passenger information systems and the supply of rolling stock.

The general scope of the Project includes, without limitation, the following:
1. Comprehensive rehabilitation of the track system, including alignment correction and material renewal, to extend its service life.
2. Comprehensive renewal of the electrical system—covering high- and medium-voltage networks, traction systems, and low-voltage systems—to meet new functional requirements for the track system, rolling stock, control systems, and support systems.
3. Comprehensive renewal of rolling stock through the deployment of up to 45 trains, increasing line transport capacity in accordance with new project requirements.
4. Implementation of train control and railway signaling systems for safe and efficient traffic management, specifically communications-based train control and telecommunications systems.
5. Rehabilitation of the structural and functional characteristics of civil works—addressing issues such as failures, fractures, deterioration of tunnel structures or concrete boxes, significant alignment loss, and deficiencies in supports or structural capacity—across tunnels, concrete structures, tracks, and stations, as necessary.
6. Comprehensive rehabilitation and modernization of stations, incorporating measures to ensure universal accessibility, operational functionality, safety, passenger flow management, and high-quality Metro spaces. This involves renewing architectural elements, vertical and horizontal circulation paths, electromechanical mobility support systems, signage, lighting, finishes, and other components necessary to guarantee adequate service conditions, comfort, and a positive user experience, in compliance with applicable regulations and new requirements.
7. Comprehensive renewal of electromechanical and support systems, incorporating updated functionalities.
8. Provision of long-term services as specified in the Sole Appendix.

The term of the Co-investment Project shall be as requested in the selected Proposal, in accordance with the Guidelines and Selection Criteria (available below in the "More Information" section).

Any individual or legal entity—whether Mexican or foreign—may participate in the selection process, either individually or jointly, in accordance with Applicable Legislation and the Guidelines.