According to 501(c)(3), fiscal sponsorship only applies to organization, not individual.
We're not sure if there is a work-around for your status but we'll try to ask around for further feedback. Cheers!
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If the security is sold, then consider it as realized. If not, consider it as unrealized until sold. Whether it is donated to a non-profit organization or not, you may consider it as list for your tax deduction for your next tax filing.