The Governments of the United States of America, the United Kingdom of Great Britain and Northern Ireland, and the Union of Soviet Socialist Republics, hereinafter referred to as the "Original Parties" [...]. (1)

The length of the opening sentence doesn't exactly give Charles Dickens a run for his money when it comes to being captivating.

The first sentence is technically lines 1-9, with a period making its first appearance just after "[...] as the Parties have stated in the Preamble to this Treaty, they seek to achieve" (9). Since this is almost a third of the document, it might be, oh, a little excessive to analyze all of it, so we're going to make an executive decision and focus on the very first part of the document, which is line 1.

The opening line does two important things here: it lists the three nations that have worked together in the creation of the PTBT, and it identifies them front and center. As we already know, they are the U.S., the U.K., and the USSR.

The second thing is that it establishes a shorthand nickname for referring to the authoring governments. They are collectively called the "Original Parties." For three nations to always be referred to as one is a sign of solidarity among them, and it also shows that they bear equal responsibility in enforcing and upholding the conditions of the treaty.