SPLITTRANSACTIONS_V1 Orphans?

[Dausto]

Hi Guys,
because of 2 categories that I was sure not used, but impossible to delete (MMEX says that are used), I checked the DB discovering that in table SPLITTRANSACTIONS_V1 there are some records with TRANSID = -1, with CATEGID exactly of the categories I tried to delete.
I understand that SPLITTRANSACTIONS_V1 is a child table of CHECKINGACCOUNT_V1 and its records must be in CHECKINGACCOUNT_V1 joined to TRANSI;, can anyone tell me if these records should be considered orphans to delete?
Probably it was caused by data porting via QIF.
Thank you.