D.C. Mun. Regs. tit. 15, r. 15-1507
The sale or transfer of effective control over a public utility for which a current Certificate has been granted shall cause nullification of the Certificate, effective as of the time at which the sale or transfer occurs, unless the sale or transfer has first been reviewed and approved by the Commission pursuant to D.C. Code § 43-801 (1990 Repl. Vol.).
For the purposes of this section, "effective control" means the ability of any person, by reason of a direct or indirect ownership interest (whether of record or beneficial) of ten percent (10%) or more of the outstanding shares or voting rights in a public utility that holds a Certificate, to direct or cause the direction of the management, operation, or policies of that public utility.
For purposes of this section, the term "person" means any individual, corporation, partnership, association, joint stock company, joint venture, trust or unincorporated organization.
Where the sale or transfer of effective control over an entity for which a Certificate has been granted, or the transfer, assignment or other disposition of stock or voting rights of an entity which is the holder of a Certificate is contemplated or intended, either voluntarily or involuntarily, a new Certificate shall be applied for by the party proposing to gain effective control.
The failure to obtain a new Certificate prior to effecting the sale or transfer of effective control over the holder of record of a current Certificate shall cause the automatic nullification of the current Certificate, effective as of the time at which the sale or transfer of effective control occurs.
D.C. Mun. Regs. tit. 15, r. 15-1507