I have one form with around 50 fields and two submit buttons, "SAVE" and "SAVE & SUBMIT". If the user clicks "SAVE", then validate only some values, eg. field1, field2. When user clicks "SAVE & SUBMIT" button, it should validate all 50 fields and submit.
<form id="myform">
    <input type="text" name="field1" />
    <br/>
    <input type="text" name="field2" />
    <br/>
    <input type="text" name="field3" />
    <br/>
    <input type="text" name="field4" />
    <br/>
    <input type="submit" id="button1" value="Save" />
    <input type="submit" id="button2" value="Submit" />
</form>
$(document).ready(function () {
    $('#button1').click(function(){          
        $("#myform").validate({             
            rules: {
                field1: {
                    required: true                         
                },
                field2: {
                    required: true                        
                }
            },
            submitHandler: function (form) { // for demo    
                alert("data saved");
            }
        });
    }); 
    $('#button2').click(function(){
        $("#myform").validate({             
            rules: {
                field1: {
                    required: true                          
                },
                field2: {
                    required: true                           
                },
                field3: {
                    required: true                         
                },
                field4: {
                    required: true                          
                }
            },
            submitHandler: function (form) { // for demo
                alert("data submited");
            }
        });
    });
});
I have created jsfiddle for this: example test