Conversion of optionally convertible debt instruments requires holders' positive consent and, where price is undetermined, an option to decline conversion. An issuer may not convert optionally convertible debt instruments into equity unless holders have given positive consent; non-response is not consent. If the convertible portion exceeds a monetary threshold and conversion price was undetermined at issuance, holders must be given an option not to convert, unless an upper price limit and justification were disclosed at issue. Where holders decline conversion, the issuer must redeem the non-converted portion within one month at not less than face value, unless redemption is already provided for in the offer document disclosures.