Privately-funded Coexis is run by former ADP Wilco men Terry Williams and Sunil Shah as chairman and CEO respectively. In September, the company was ranked at number 92 in the Sunday Times Tech Track 100 list after achieving 40.08% compound revenue growth in the past three years and doublings its staff numbers to 100 over the past year.

Atos Euronext Market Solutions acquired a 19.5% stake in Coexis in 2006 with an option to buy the entire company in late 2008. But this deal floundered when the Dutch company was broken up earlier this year and all of the shares in Coexis were bought back by the group's private investors.

Coexis' Syn~ component-based settlement and workflow automation software has been deployed by CLSA, Penson and Mitsubishi among others. It has been applied for multi-site, middle and back office securities processing, enterprise-wide reference data management, corporate actions, multi-exchange and multi-CSD processing.

GBST's securities transaction processing and client accounting software is used by market participants to process approximately A$130 billion of ASX trades every month and its fund administration software is used to administer funds valued at more than A$150 billion in Australia and the United Kingdom.

The company says the acquisition of Coexis will enable it to broaden its portfolio of products and services and propel its global expansion plans.

Sunis Shah, Coexis CEO says: "Our Syn~ technology will provide GBST with a modern, flexible and scalable solution for modelling business processes and bringing future products to market far more rapidly than traditional methods. This deal would significantly increase GBST's global reach and expansion via Coexis' existing international customers, prospects and distribution channels."

Under the deal, Coexis will continue to work with established partners such as Serisys Solutions Limited in Asia as well as correspondent clearers providing white labelled services to brokers.