I'm referring to the contractors providing the TOCs' online TISs.
The Trainline are probably the biggest provider, holding the contract for:
- ScotRail
- TfW
- West Midlands Trains
- Greater Anglia
- EMR
- CrossCountry
- Northern
ATOS hold the contract for:
- GWR
- SWR
- TPE
- Hull Trains
- Lumo
- RSTL
IBM hold the contract for:
Then there are four more providers whose names I'm not entirely sure of, who respectively hold the contracts for GTR and Southeastern; Chiltern and Grand Central; LNER; and Caledonian Sleeper. And then there's National Rail Enquiries, though that's not strictly a TIS.
Now that list includes some TOCs which aren't under DfT control, but clearly there are a multitude of providers and many different contracts in place. Amalgamating it into one large contract would likely save quite a bit of money and that's what the government has said it intends to do under GBR.