onBeforeSpan

fires before cells are merged

boolean onBeforeSpan(number row,number column,array size, [string page] );

row

numberthe number of the row that the span starts with column

numberthe number of the column that the span starts with size

arraythe number of cells in col and row spans pagestringthe name of the sheet

boolean

returning false will prevent cells merging

$$("ssheet").attachEvent("onBeforeSpan", function(row, column, size, page){
    // some code here
    return true;
});

Details

Return false to block cell merging.