How do you create rules for jquery form validate plugin with names that are arrays?

You need to wrap the name of the input (in this case data[]) in quotes

$('#myform').validate({
  rules : {
    'data[]': { required: true, minlength: 1 }
  }
});

see the documentation here for Field with complex names (Brackets Dots): http://docs.jquery.com/Plugins/Validation/Reference#Fields_with_complex_names_.28brackets.2C_dots.29