Shares in Saudi Arabia's Arabian Shield Cooperative Insurance 8070.SE , which have been trading near 20-month lows, rise 3.4 pct to 20.12 riyals in early, unusually heavy trade.

Company said state utility National Water Co had engaged it to provide health insurance services to its employees for one year; value of contract is 104.5 million riyals ($27.9 million).

Company's gross written premiums had dropped 43 percent on year in second quarter to 93.4 million riyals.

Saudi stock index .TASI gains 1.1 pct.

(Reporting by Andrew Torchia) ((andrew.torchia@thomsonreuters.com; +9715 6681 7277; Reuters Messaging: andrew.torchia.thomsonreuters.com@reuters.net))