The 12 institutions filed an application with the Court of Appeal offering to provide their perspective on how the existing policy could adversely affect Hong Kong as an international financial centre by limiting the pool of quality foreign employees willing to relocate.
But the court found that their input would most likely repeat the points QT may wish to make anyway and dismissed the proposed application.
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"The court can easily see the more rounded picture from the employers' perspective without their input," Mr Justice Jeremy Poon Shiu-chor wrote on behalf of chief judge Andrew Cheung Kui-nung and vice-president Johnson Lam Man-hon.
The 12 institutions are: ABN AMRO Bank NV; AIG Insurance Hong Kong; Australia and New Zealand Banking Group; the Bank of New York Mellon; Credit Suisse (Hong Kong); Goldman Sachs Services (Asia); Royal Bank of Canada; Societe Generale; State Street Bank & Trust; Blackrock Asset Management North Asia; Morgan Stanley Asia; and Nomura International (Hong Kong).
QT, who moved to Hong Kong in late 2011 with her same-sex partner SS, had applied for judicial review after the Immigration Department rejected her application for a dependent visa because it did not recognise same-sex relationships.
The pair took the case to court, arguing the decision was discriminatory and breached the Basic Law and the Bill of Rights Ordinance.
But the lower Court of First Instance sided with the Hong Kong Immigration Department in finding the overseas concept of "spouses" – which QT's lawyers argued should be broader than the wedlock between a man and woman – did not apply to Hong Kong.
QT's appeal hearing will be heard next Thursday and Friday.