We’re working with ASP.net. The minimal date (null) value is 0001-01-01 00:00:00 (transformed to the Webix format). The datepicker transforms this to 01-01-2001. I’ve reproduce the issue in a snippet: Code Snippet. How can we solve this in a easy manner? 
Which result you want to see when the date like “0001-01-01” is provided ?
Of course, the valid behavior will be to show the year 1, but I doubt that it will be helpfull in your case.
By the way, providing the null value ( when you have a null in database ) results in the correct empty datepicker
I expect an empty date picker since this is the min value.
if you are unable to use null value as empty, then try to set JSON serializer’s default value policy to ignore.