Former Billion International Holdings boss Simon Chan Ying-ming has been hit with further litigation for an alleged unpaid loan. Already facing charges of operating an unlawful deposit-taking business, Chan was also recently the focus of a stock-exchange notice seeking to contact him. A High Court writ filed yesterday by Billion Enterprise is seeking to recoup $597,638 - the balance of an outstanding loan. Billion Enterprise allegedly loaned $700,000 to Chan, trading as Billion Finance. Chan agreed to execute a deed of sub-mortgage in favour of Billion Enterprise. Chan's solicitors, Philip Pang & Co, acted on behalf of both parties to prepare the sub-mortgage, the writ said. However, the writ states that the solicitors failed to have the sub-mortgage registered in the land registry. The solicitors agreed to pay $700,000 in settlement of Billion Enterprise's loss and damages, the writ said. Only $400,000 has been paid, according to the writ. Billion Enterprise is seeking the balance of the settlement plus interest, amounting to $597,638 against both Chan and the solicitors. It is also seeking interest and costs.