My hypothetical process of how this process could come up is as follows:

1] DM decides if the are interested in taking on EDIG... and follows with yes

2] Before they take EDIG on, they develop a list of companies they may end up litigating against and see if they are already representing them

3] DM expands the scope beyond what was initially seen at the time of engagement and as new suits are added it becomes evident that company X, that DM has represented/represents will have a suit filed against them.

4] Decision time how to handle the suits between the IP firm, and corporations....

As Silver stated, accidents happen, and things are always dynamic and changing. As more research is done, companies may get added to the list or removed throughout the process.