Licence in composer.json for Magento 2 marketplace

Question

What type of licence should I use to sell my module in Magento marketplace?

Here is my example. How it could be improved?

{
    "name": "vendor/module",
    "description": "Desc",
    "type": "magento2-module",
    "version": "1.0.0",
    "license": [
    ],
    "require": {
        "php": "~5.5.0|~5.6.0|~7.0.0",
    },
    "extra": {
        "map": [
            [
                "*",
                "vendor/module"
            ]
        ]
    }
}

Answer 1

For Magento 1 there are different types of licence are available, as per the screenshot

For Magento 2 If you are selling as open source then you can use OSL-3.0 , currently I have free extension from fooman and they are using this composer

{
  "name": "fooman/printorderpdf-m2",
  "description": "Print the order as a pdf from the admin",
  "type": "magento2-module",
  "license": "OSL-3.0",
  "version": "2.0.3",
  "autoload": {
    "psr-4": {
      "Fooman\\PrintOrderPdf\\": "src/"
    },
    "files": [
      "src/registration.php"
    ]
  },
  "autoload-dev": {
    "psr-4": {
      "Fooman\\PrintOrderPdf\\Test\\": "tests/unit/Test/"
    }
  },
  "repositories": [
    {
      "type": "composer",
      "url": "https://repo.magento.com/"
    }
  ],
  "require": {
    "magento/module-backend": "~100.1.0",
    "magento/module-sales": "~100.1.0"
  },
  "require-dev": {
    "phpunit/phpunit": "^4.5"
  },
  "minimum-stability": "dev",
  "prefer-stable": true
}

you can update your composer based on your extension. Fore more perfect answer I think some extension development company can give you more details about licence.