The number sending PPI Insurance Claim Spam Text is 07747124749
It appears from the replies that any replies to this number are then sold on to various other PPI claim companies, a very dubious practice if they are obtaining leads gathered through deception like this.
Numbers used by the PPI claim companies to follow up on fake PPI claims are:
Companies operating in this way appear to be Ucall, Flame Communications
Flame Communications even placed a presentation online showing how great their spamming service was for generating leads that could produce £250,000 income from commission on PPI claims.