Complex sentence: In December 2010, IIROC imposed penalties on both Blackmont Capital and Duke for splitting commissions with people associated with a client without the client's written consent, and for not disclosing the commission-sharing arrangement with its clients.
Split into simpler sentences: In December 2010, IIROC imposed penalties on both Blackmont Capital and Duke for splitting commissions with people associated with a client without the client's written consent. IIROC also imposed penalties for not disclosing the commission-sharing arrangement with its clients.