Director liability for unrecovered GST: private company directors can be jointly liable unless they rebut gross neglect. Directors of a private company are jointly and severally liable for tax, interest or penalty on supplies if those amounts cannot be recovered from the company, unless the director proves the non-recovery is not due to gross neglect, misfeasance or breach of duty; upon conversion to a public company, that director liability does not apply to amounts not recovered before conversion, though personal penalties on directors remain unaffected.