What defines the limitations of who can file a transitional program for covered business method patents?

The correct answer outlines that only parties who previously filed for infringement can initiate a transitional program for covered business method patents. This limitation is rooted in the purpose of the program, which is designed to provide a mechanism for those involved in business method patent disputes to challenge the validity of such patents.

By restricting the eligibility to those who have previously pursued infringement claims, the program ensures that parties are directly affected by the patent in question. This encourages the resolution of disputes that have already surfaced in practical settings, ensuring that the review process is relevant and necessary, rather than open and vague, which could lead to frivolous claims or unnecessary challenges by parties without a vested interest in the outcome.

The other options do not accurately reflect the requirements set by the patent system. For instance, patent owners seeking to modify their claims or individuals who have not engaged in any infringement disputes do not fall under this specific eligibility requirement. The requirement for undergoing post-grant review or creating an unrestricted application process would undermine the focused nature of the program, which is intended specifically for those already engaged in litigation regarding the patents in question.