Heritage Auctions unaware of any treaty?

Greg Rohan, president of Dallas based Heritage Auctions commenting on his firm's selling of a Mongolian fossil despite a temporary restraining order is quoted in The New York Observer as saying he was confident that the transport of the skeleton to the U.S. was legal, because:

“We and our counsel are not aware of any treaties under which the sale would be illegal,” Mr. Rohan said.

Well, that depends what export licences they have for it, so far they have refused to say. One international convention of no small import is the 1970 UNESCO Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property. The president of Heritage Auctions surely is not "unaware" of that? Yet what figures in the first point of the first article of that convention? In case he's forgotten I'll quote it:

 For the purposes of this Convention, the term `cultural property' means property which, on religious or secular grounds, is specifically designated by each State as being of importance for archaeology, prehistory, history, literature, art or science and which belongs to the following categories: (a) Rare collections and specimens of fauna, flora, minerals and anatomy, and objects of palaeontological interest; [...]

Then the president of heritage Auctions surely cannot, if he values the reputation of his firm, to be "unaware" of the content of Article 3:

The import, export or transfer of ownership of cultural property effected contrary to the provisions adopted under this Convention by the States Parties thereto, shall be illicit.

The USA is a state party of that Convention, so, where are the export licences? Showing how it left Mongolia, where it was before bought by the Brit and its legal export from the UK to Florida?

Laura L. Griffin, 'T-Rex Wreck: Mongolian Representative Disrupts Skeleton Auction', New York Observer 21st May 2012.

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