Scope of blank nodes in TriG?

Example Document 3 in the TriG spec[1] shows the same blank node label being
used in different graphs. My interpretation of the example is that those
blank nodes are distinct, i.e. the scope of blank node labels is the graph
not the TriG document. How do the main graph stores behave? Is it possible
to put the same blank node into two different graphs? If so, this
information would not be serializable in TriG if my interpretation is
correct.




[1] http://www4.wiwiss.fu-berlin.de/bizer/trig/

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Ian Davis, Chief Technology Officer, Talis Group Ltd.
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