What costs does a shareholder risk if they bring an oppression claim and lose in Ontario?

Like most civil litigation in Ontario, oppression claims generally follow the loser-pays principle for legal costs — if a shareholder brings an oppression claim under the OBCA and is unsuccessful, a court will typically order them to pay a portion of the successful party's legal costs, in addition to having spent their own legal fees pursuing the claim without any recovery. Costs awards in Ontario civil litigation do not usually cover the winning side's full actual legal bill; courts award costs on a partial-indemnity basis by default, covering a substantial portion but not the full amount, though a court has discretion to award higher costs in some circumstances, such as where a claim was found to be unreasonable or conducted improperly.

Because oppression cases involving closely-held corporations can become lengthy and expensive, involving detailed financial and valuation evidence, document production, and sometimes cross-examinations, the actual costs at risk on both sides can be significant relative to the value of the shares or relief in dispute, especially in a smaller private company. This cost exposure is one of the practical reasons many oppression disputes get resolved through negotiation or mediation, and it is worth discussing realistic cost exposure with a lawyer alongside the merits of the claim before deciding whether to proceed.