Using the PUT method with Express.js

You may be lacking the actual update function. You have the put path returning the result back to the client but missing the part when you tell the database to update the data.

If you're using MongoDB and ExpressJS, you could write something like this :

app.put('/api/:company', function (req, res) {
    var company = req.company;
    company = _.extend(company, req.body);
    company.save(function(err) {
    if (err) {
        return res.send('/company', {
            errors: err.errors,
            company: company
        });
    } else {
        res.jsonp(company);
    }   
  })
});

This mean stack project may help you as it covers this CRUD functionality which I just used here swapping their articles for your companies. same same.

Your callback function has the arguments in the wrong order.

Change the order of callback to function(req, res). Don't use function(res, req).