Hi guys,
I disagree. Absent an express term in a shareholder agreement (IP rights would not be dealt with in a constitution) any code written by an individual, whether an employee or contractor or shareholder or owner or person on the street, will belong to that person by default. Therefore, unless it is expressly provided for in the constitution that a shareholder can "pay" for their shares in the company through IP contributions, IP contributions will not be deemed to contribute toward the share-purchase price.
This is why there is always an IP transfer/attribution clause in the shareholders' agreement for joint ventures where company shareholders contribute IP or resources into a new joint venture company.
When starting up a company, one must deal with IP rights expressly, otherwise, things get messy. If the company itself purchases an IP right or licence, then the company, and not the shareholders, will own it.