In the Corax records, does anybody know what the "Corax Search Type" column means, I've seen two values "F" and "B" but can't find any documentation to say what the two mean.
I understand that you are using the Corporate Actions message type in TRTH version 1. Below is the related information in the Tick History Corporate Actions Migration Guide document. The document can be downloaded from the Tick History home page.
The current version of Tick History (version 1) will be withdrawn and retired on 31 December 2017. If you are still using the TRTH version 1, we would recommend that you migrate to the TRTH version 2. Please see more information about the TRTH version 2 API in this link.