Dec 18 (Reuters) - Covata Ltd CVT.AX :
* 20,000 user enterprise deal for 3 years CVT.AX
* Says management has set a target of 8,250 signed and revenue generating end user seats for q2fy16
* Says billing for this major contract will begin in January 2016 for three years
* Source text for Eikon ID:nASX27rd9G