Your journey may consist of one or more transport contracts. If you buy several tickets simultaneously in a single transaction, each ticket constitutes a separate transport contract. Any claims under passenger law will, therefore, only apply to that particular transport contract.
A traveller books a trip from Groningen to Bordeaux and receives 3 tickets for this purpose. The 3 tickets all constitute a separate transport contract.
Traveller's rights if his trip from Groningen to Rotterdam is delayed, causing him to miss his Thalys and also his transfer to the TGV in Paris:
The train journey from Groningen to Rotterdam is a transport contract with NS Reizigers. The delay does not change the transport contract with Thalys or TGV. As a result, if there is a delay on the Groningen - Rotterdam section and the passenger misses the connection to the Thalys and TGV, the passenger is not entitled to a possible refund of the Thalys ticket or TGV ticket or to cash back on delay (GTBV). However, the passenger may be eligible for Money Back on Delay (GTBV) for the trip from Groningen to Rotterdam.