Can The Trustee Be A Beneficiary or Hold Beneficial Interest Certificates (BIC)
Yes; however, a trustee cannot be the sole (only) beneficiary. There should be at least one other beneficiary - which may also be another trust that the trustee sits on the Board of Trustees for. Further, the beneficiaries may have the lot of assets divided unequally among them (99% for a trustee, 1% for the other entity).
NOTE: While a trustee can hold Beneficial Interest Certificates. It is better if a trustee does not hold any BICs. Holding BICs terminates the ability for the trustee to exchange property into the trust, doing so would result in a fraudulent conveyance.