Developing/publishing software before and after date of hire
<p>Assume that the following software did not infringe laws or other parties' IP.  If an employee signs a letter at the date of hire which turns over all IP ownership to the employer (including inventions, trade secrets, software,....), but had already developed and published results of software prior to hire date, can the employer claim ownership to such software?  </p>

<p>Regarding software development after date of hire (offsite, on weekends, no use of employer resources), could one gather together research articles containing mathematical equations from the published literature and pay contracted programmers to develop software using such equations?  In this case, the IP used was never developed by the employee and the employer never owned the IP that was openly published in the public domain.  </p>

<p>Employer claims to copyright of works created by their employees is limited to work done in the course of that employment: it does not extend to all works created by the employee, especially works created before the employment relation existed. However an employer can also require assignment of IP rights not covered by work-for-hire law as a condition of employment. The extent of such claims is governed by the language of the contract, and might be deemed invalid as "unconsionable". However, depending on the country you are in, it is possible that there are limits on this, governed by labor law.</p>

intellectual-property software