In a recent liaison meeting with AILA, the USCBP Buffalo, NY office clarified that where a TN visa applicant is seeking entry to perform work for multiple employers, USCBP will generally prefer to issue separate I-94 cards for each employer as opposed to a single I-94 card covering all employers. AILA/CBP Buffalo, AILA InfoNet Doc. No. 14020748 (posted 2/7/14).
In September 2013, the CBP national office confirmed that individuals may work for multiple employers in the U.S. at the same time. NAFTA Guide For TN and L Applicants (June 2012), AILA InfoNet Doc. No. 13091643 (posted 9/16/13). While noting that applicants needed to provide separate employment letters for each potential employer, CBP stated that the processing of the applications were considered a "single event" and that only one filing fee would be charged. Id. CBP would not charge a filing fee for each employment application. Id.