In Schnier v Canada (Attorney General), 2016 ONCA 5, the Court held that an amount of tax owing (about $4.4 million) was a contingent claim because the relevant assessments were under appeal to the Tax Court. As a result, the Court upheld a discharge from bankruptcy for the taxpayer where the Trustee had admitted only $71,170 of the claim. I don’t know enough about bankruptcy to say whether the resulting is surprising, but I can’t imagine the CRA would be happy about it.
The assessments, by the way, went back to 1989. They were confirmed only in October 2011 (for a yacht shelter) and January 2013 (for a computer software shelter).