<form:form name="form" action="/myAction" method="POST" commandName="model1">
    <form:input path="property"/>
    ....
    <input type="submit" value="Submit"/>
</form:form>

@SessionAttributes("model2")
class Controller {
    @RequestMapping(value = "/myAction", method = POST)
    public String submitEditSite(final @ModelAttribute(value = "model1") Model1 model1,
                                 final @ModelAttribute(value = "model2") Model2 model2) {
        ....
        return "redirect:/home";
    }
}

class Model1 {
    private String property;
}
class Model2 {
    private String property;
}

@InitBinder("model2")
  public void initBinder(WebDataBinder binder) {
    binder.setDisallowedFields("*");
  }