A fair number of US law departments keep lists of domestic preferred firms, which law firms they turn to unless there are extraordinary circumstances. Similar lists are much less common for firms that are based outside the US. According to Law Firm Inc., Vol. 5, May 2007, at 38-9, “Only a small number (15 percent) of U.S companies and divisions maintain a formal preferred list of overseas firms and/or lawyers. 29 percent have an informal preferred list and 30 percent have an informal list, while 26 percent do not maintain a list of firms or individual overseas legal service providers.”
This data came from an ALM survey of more than 200 “key corporate decision-makers involved in the purchasing of overseas legal services.” Almost half of the companies would be in the Fortune 1000 in terms of revenue.
Even when law departments claim they keep track of outside counsel, I would not be surprised if the lists are kept up very haphazardly, rarely pruned, not subjected to evaluations, and contain duplicates.