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Introduction: Several studies have suggested that differential weakness in muscles supplied by the same motor nerve supports the diagnosis of multifocal motor neuropathy (MMN)., Methods: We describe the clinical, electrophysiological, neuroimaging, and laboratory findings of patients with a lower motor syndrome whose clinical presentation included differential finger extension weakness that we have seen in our neuromuscular clinic., Results: We identified 3 patients with hand weakness and 1 patient with asymmetric weakness of the upper extremity. Conduction blocks (CBs) were identified in 1 patient. Anti-GM1 immunoglobulin M antibodies were detected in 2 of the 3 patients tested. Only 1 patient responded to intravenous immunoglobulin (IVIg). Rituximab was administered in another patient, but we did not detect a response., Conclusions: We suggest that differential finger extension weakness is a feature that may be seen in MMN, even in the absence of CB or response to IVIg. Muscle Nerve 55: 433-437, 2017., (© 2016 Wiley Periodicals, Inc.)